Hey guys. I love using computer craft, and I was planning on doing some pretty cool stuff with GUIs and Touchscreens, but I later realized I couldn't install my favorite ComputerCraft Widget API because it's a public server. Do you think you could do that? Installing it would make this (very useful) api accessible to everyone on the server as well I think. Link to API: Widget Api Full-Featured Gui - ComputerCraft | Programmable Computers for Minecraft
Dark Buttons! - Easy bundled cable control gui for monitors - ComputerCraft | Programmable Computers for Minecraft That is what I used to use and it doesn't need a server side API installed to use it. It works similarly to the screenshot of what you posted. I used to use it on ultimate and I'm not sure it was kept updated, but I'd bet there is something out there similar to this (incase we decide not to install the API)
In general, you don't need to modify the rom if you want to use custom APIs. It's always possible to store it somewhere else in the file system. True, due to the stupidity of computercraft's architecture, the APIs only do get loaded automatically if they reside in the apis folder. However, up to now I've always been able to find a ways around those problems. So I don't really see the necessity.