We're currently aware of an ongoing problem with "tile entities" duplicating. The reason is really technical, so I'll spare you the details, but the effect is:
tick rate slows
the server freezes due to "crafting"
the server stalls entirely
Crafting is not actually slow -- it's this problem. It only affects Nether too, so it baffles me. Over the next week, I will find some time to add some code to the server to diagnose the cause. We can unload Nether to temporarily fix it without restarting the server.
We've managed to quell most of the crashes and stalls that have plagued Alice for the past week. We've nearly reached the level of "crash suppression" that we had on previous Alice versions, and we've added a stall detector that will detect when the server has frozen, attempt to recover the server, but then restart the server if recovery fails (while also broadcasting messages the entire time so you don't just time out).
Crafting still has the potential to freeze the server, so we're still looking into that.
GregTech (on the client) also starts much faster now. I think some people have had load times reduced from 15 minutes to 6. We'll see if we can improve it even further, although the rest of the modpack also takes a significant amount of time.
As for Vincent, I'll see if I can get it up next week.