After an update today the nexus chalk from Ars Magica is gone. It is requested for some quests in the questbook. All nexi don't work anymore. Instead of turning in orbs for quests, some colored runes are now required, although the text in the quest still refers to orbs which were required before the update. It is no longer possible to change the casting mode. Casts can only be castet every ~4 seconds. There may be more problems f.e. creating spells which i haven't tested yet, but heared from another Player.
For the record, the nexi were replaced with the obelisks, which worked as intended, casting mode can only be changed when you have a spell selected, and creating, as well as casting spells worked fine.
The replacement for the essence nexus is the obelisk, which is also used in rituals for the other two nexi. Both of these rituals use the new Wizard's Chalk, which is also used to upgrade each nexus by drawing a 'circle' around it. I can confirm that this works, at least for the light nexus and obelisk, as I tested it during the temporary update. The rituals are demonstrated in this video from Mithion, at about 3 minutes in.
