Welcome back chocohead, im happy to see the new version of optifabric released!

when I tried to run the game (with only this in my mods folder)

the game crashed giving me this on the launcher:

The game crashed whilst mouseclicked event handler
Error: java.lang.RuntimeException: Mixin transformation of net.minecraft.class_446 failed
Exit Code: -1

this also shows up in logs

I have the same problem.

Same here