While trying to narrow down a problem trying out the new MFR, I only loaded three mods in a simple pack. I got this crash. Looks to me like it's trying to init the MFR fluids and fails, could be wrong.

https://pastebin.com/keZ3Kjs6

Literally came here to post the same crash. :D Can confirm this is happening on 2.9.0B1-221

yea trying to place some of the machines also crashes the game

well actually it doesnt crash it freezes

Well, 4.1.6 of core was supposed to include a commit I had made about an hour before it was released, but apparently it did not.

This is resolved with CoFHCore 4.1.6.10.