Here is the crash report. This happened when was searching for the flood gate in the creative menu.

Update: I had another, related crash, although I'm not sure if this was caused by the same thing.

Can anyone reproduce this?

http://hastebin.com/cunojawamo.md

Bunch of mods installed, rotarycraft, pneumaticcraft, twilight forest, forestry, etc. I think there's a list at the end of the paste...

Working on reliable reproduction steps...

Hmm, that log also includes some other things, I believe the actual crash at the end was during searching like this one, which I can't get to reproduce now...

@BionicFelps Your ID map seems to be broken, as well as your fluid registry...?

Could be, I'm working on a modpack, and I'm at a stage where I just stapled together a load of various mods... I believe the DragonAPI (rotarycraft coremod) does some odd things with item names...

I was able to reproduce the crash that set the chain of crashes off in that log, which was sticking a wooden pipe on a rotarycraft water reservoir, made a separate issue report for that.

Upon closer inspection... The reason I couldn't reproduce it with buildcraft was it was because it was enderstorage causing the issue in (my) case... The search issue that is.