I'm using Redpower2, Buildcraft, Thaumcraft 2 and Mystcraft. Often, it takes a lot to generate a new Myst era, then when it renders it slows to a crawl (like 1 frame per 15 seconds), but I just try my hardest to press ESC and then spam mousebutton the Quit to main menu button, eventually it works, I exit Minecraft, reload, and it's all fine and dandy.
May be a memory thing, my Java is currently capped at 2 GB. Could try to increase it to 3 to see what happens.
I'm using the same as you but without Buildcraft and get the same problem with some Mystcraft eras. One strange era was all jungle but each rubber tree had it's top missing. They were like giant rubber wooden obelisks.
Anyone know how to get Thaumcraft crystals and monoliths to spawn in Mystcraft eras? Some have them, some don't, and I can't find any rhyme or reason to it.
Yeah my first era was like that. It was also a Caveworld, which I think means it was basically a big chunk of blocks (the spawn was at the TOP, layer 120 or so) which was probably the reason the rubbertrees were chopped.
Caveworld, minus caverns, I guess. But it had a star fissure.
Also, I think Thaumcraft crystals are dependent on underground features. Like, the era has to have Caverns or something. Then it will spawn crystals (not just IN the caverns), someone mentioned that a few pages ago I think?
Also, RE: The water pump thingy, silly me forgot about the FILLER! Now I just need to have some air pocket below where I can plant my landmarks and presto, water gone and a nice stone brick box around the removed area. Ladders seem to be just right for that.