The Steve's Workshop production table gives me a "fatal error has occurred" message when I attempt to open the GUI. It works in a single player world without issues. Here is the log: Spoiler [16:57:16] [Client thread/ERROR] [FML]: Exception caught during firing event net.minecraftforge.client.event.GuiOpenEvent@264841a0: cpw.mods.fml.relauncher.ReflectionHelper$UnableToFindMethodException: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:32) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.slots.SlotHandler.getSlotBasedOnGui(SlotHandler.java:20) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.EventHandlerClient.openGuiEvent(EventHandlerClient.java:108) ~[EventHandlerClient.class:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler_597_EventHandlerClient_openGuiEvent_GuiOpenEvent.invoke(.dynamic) ~[?:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54) ~[ASMEventHandler.class:?] at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:138) [EventBus.class:?] at net.minecraft.client.Minecraft.func_147108_a(Minecraft.java:775) [bao.class:?] at cpw.mods.fml.client.FMLClientHandler.showGuiScreen(FMLClientHandler.java:445) [FMLClientHandler.class:?] at cpw.mods.fml.common.FMLCommonHandler.showGuiScreen(FMLCommonHandler.java:303) [FMLCommonHandler.class:?] at cpw.mods.fml.common.network.internal.FMLNetworkHandler.openGui(FMLNetworkHandler.java:94) [FMLNetworkHandler.class:?] at net.minecraft.entity.player.EntityPlayer.openGui(EntityPlayer.java:2209) [yz.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:16) [OpenGuiHandler.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:11) [OpenGuiHandler.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:98) [SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:101) [SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103) [MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) [MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) [DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) [EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1590) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:961) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:887) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_60] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_60] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_60] at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_60] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.11.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.11.jar:?] Caused by: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:101) ~[launchwrapper-1.11.jar:?] at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_60] at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_60] at java.lang.Class.forName0(Native Method) ~[?:1.7.0_60] at java.lang.Class.forName(Class.java:190) ~[?:1.7.0_60] at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:27) ~[SlotHandler.class:?] ... 37 more [16:57:16] [Client thread/ERROR] [FML]: Index: 3 Listeners: [16:57:16] [Client thread/ERROR] [FML]: 0: NORMAL [16:57:16] [Client thread/ERROR] [FML]: 1: ASM: main.launchgui.GuiEventHandler@6bb26d10 openMainMenu(Lnet/minecraftforge/client/event/GuiOpenEventV [16:57:16] [Client thread/ERROR] [FML]: 2: ASM: tterrag.core.client.gui.GuiEventHandler@5aa3eac9 onGuiOpen(Lnet/minecraftforge/client/event/GuiOpenEventV [16:57:16] [Client thread/ERROR] [FML]: 3: ASM: net.lomeli.trophyslots.client.EventHandlerClient@1893018f openGuiEvent(Lnet/minecraftforge/client/event/GuiOpenEventV [16:57:16] [Client thread/ERROR] [FML]: 4: ASM: vswe.production.nei.OverlayWrapper@d16c01d onOpen(Lnet/minecraftforge/client/event/GuiOpenEventV [16:57:16] [Client thread/ERROR] [FML]: OpenGuiHandler exception cpw.mods.fml.relauncher.ReflectionHelper$UnableToFindMethodException: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:32) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.slots.SlotHandler.getSlotBasedOnGui(SlotHandler.java:20) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.EventHandlerClient.openGuiEvent(EventHandlerClient.java:108) ~[EventHandlerClient.class:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler_597_EventHandlerClient_openGuiEvent_GuiOpenEvent.invoke(.dynamic) ~[?:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54) ~[ASMEventHandler.class:?] at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:138) ~[EventBus.class:?] at net.minecraft.client.Minecraft.func_147108_a(Minecraft.java:775) ~[bao.class:?] at cpw.mods.fml.client.FMLClientHandler.showGuiScreen(FMLClientHandler.java:445) ~[FMLClientHandler.class:?] at cpw.mods.fml.common.FMLCommonHandler.showGuiScreen(FMLCommonHandler.java:303) ~[FMLCommonHandler.class:?] at cpw.mods.fml.common.network.internal.FMLNetworkHandler.openGui(FMLNetworkHandler.java:94) ~[FMLNetworkHandler.class:?] at net.minecraft.entity.player.EntityPlayer.openGui(EntityPlayer.java:2209) ~[yz.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:16) ~[OpenGuiHandler.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:11) ~[OpenGuiHandler.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:98) ~[SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:101) [SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103) [MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) [MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) [DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) [EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1590) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:961) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:887) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_60] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_60] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_60] at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_60] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.11.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.11.jar:?] Caused by: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:101) ~[launchwrapper-1.11.jar:?] at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_60] at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_60] at java.lang.Class.forName0(Native Method) ~[?:1.7.0_60] at java.lang.Class.forName(Class.java:190) ~[?:1.7.0_60] at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:27) ~[SlotHandler.class:?] ... 37 more [16:57:16] [Client thread/ERROR] [FML]: HandshakeCompletionHandler exception cpw.mods.fml.relauncher.ReflectionHelper$UnableToFindMethodException: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:32) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.slots.SlotHandler.getSlotBasedOnGui(SlotHandler.java:20) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.EventHandlerClient.openGuiEvent(EventHandlerClient.java:108) ~[EventHandlerClient.class:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler_597_EventHandlerClient_openGuiEvent_GuiOpenEvent.invoke(.dynamic) ~[?:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54) ~[ASMEventHandler.class:?] at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:138) ~[EventBus.class:?] at net.minecraft.client.Minecraft.func_147108_a(Minecraft.java:775) ~[bao.class:?] at cpw.mods.fml.client.FMLClientHandler.showGuiScreen(FMLClientHandler.java:445) ~[FMLClientHandler.class:?] at cpw.mods.fml.common.FMLCommonHandler.showGuiScreen(FMLCommonHandler.java:303) ~[FMLCommonHandler.class:?] at cpw.mods.fml.common.network.internal.FMLNetworkHandler.openGui(FMLNetworkHandler.java:94) ~[FMLNetworkHandler.class:?] at net.minecraft.entity.player.EntityPlayer.openGui(EntityPlayer.java:2209) ~[yz.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:16) ~[OpenGuiHandler.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:11) ~[OpenGuiHandler.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:98) ~[SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:101) [SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103) [MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) [MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) [DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) [DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) [EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1590) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:961) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:887) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_60] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_60] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_60] at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_60] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.11.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.11.jar:?] Caused by: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:101) ~[launchwrapper-1.11.jar:?] at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_60] at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_60] at java.lang.Class.forName0(Native Method) ~[?:1.7.0_60] at java.lang.Class.forName(Class.java:190) ~[?:1.7.0_60] at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:27) ~[SlotHandler.class:?] ... 37 more [16:57:16] [Client thread/ERROR] [FML]: There was a critical exception handling a packet on channel FML cpw.mods.fml.relauncher.ReflectionHelper$UnableToFindMethodException: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:32) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.slots.SlotHandler.getSlotBasedOnGui(SlotHandler.java:20) ~[SlotHandler.class:?] at net.lomeli.trophyslots.client.EventHandlerClient.openGuiEvent(EventHandlerClient.java:108) ~[EventHandlerClient.class:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler_597_EventHandlerClient_openGuiEvent_GuiOpenEvent.invoke(.dynamic) ~[?:?] at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54) ~[ASMEventHandler.class:?] at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:138) ~[EventBus.class:?] at net.minecraft.client.Minecraft.func_147108_a(Minecraft.java:775) ~[bao.class:?] at cpw.mods.fml.client.FMLClientHandler.showGuiScreen(FMLClientHandler.java:445) ~[FMLClientHandler.class:?] at cpw.mods.fml.common.FMLCommonHandler.showGuiScreen(FMLCommonHandler.java:303) ~[FMLCommonHandler.class:?] at cpw.mods.fml.common.network.internal.FMLNetworkHandler.openGui(FMLNetworkHandler.java:94) ~[FMLNetworkHandler.class:?] at net.minecraft.entity.player.EntityPlayer.openGui(EntityPlayer.java:2209) ~[yz.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:16) ~[OpenGuiHandler.class:?] at cpw.mods.fml.common.network.internal.OpenGuiHandler.channelRead0(OpenGuiHandler.java:11) ~[OpenGuiHandler.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:98) ~[SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:101) ~[SimpleChannelInboundHandler.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) ~[DefaultChannelHandlerContext.class:?] at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103) ~[MessageToMessageDecoder.class:?] at io.netty.handler.codec.MessageToMessageCodec.channelRead(MessageToMessageCodec.java:111) ~[MessageToMessageCodec.class:?] at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:337) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:323) ~[DefaultChannelHandlerContext.class:?] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:785) ~[DefaultChannelPipeline.class:?] at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:169) ~[EmbeddedChannel.class:?] at cpw.mods.fml.common.network.internal.FMLProxyPacket.func_148833_a(FMLProxyPacket.java:77) [FMLProxyPacket.class:?] at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) [ej.class:?] at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273) [bje.class:?] at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1590) [bao.class:?] at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:961) [bao.class:?] at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:887) [bao.class:?] at net.minecraft.client.main.Main.main(SourceFile:148) [Main.class:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_60] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_60] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_60] at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_60] at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.11.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.11.jar:?] Caused by: java.lang.ClassNotFoundException: net.lomeli.trophyslots.client.slots at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:101) ~[launchwrapper-1.11.jar:?] at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_60] at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_60] at java.lang.Class.forName0(Native Method) ~[?:1.7.0_60] at java.lang.Class.forName(Class.java:190) ~[?:1.7.0_60] at net.lomeli.trophyslots.client.slots.SlotHandler.invokeMethod(SlotHandler.java:27) ~[SlotHandler.class:?] ... 37 more
If you are able to setup a forge server with agrarian skies 2 then feel free to do it and test if you have the same issue there.