The game seems to crash after loading into a world with the following error:
https://pastebin.com/wCrM36wP
(I'm aware that this is an alpha build, I was curious to see if it works with my modpack)

And as far as I have tested, which wasn't very in-depth, Welcome to the Jungle seems to produce the same kind of issue with practically the same error.

I don't have a crash when loading in to a world, however FP2 doesn't generate any distant terrain.