Hi.
I am Japanese, so my English may be weak.
This crash report is output when Project Red wires or machines are placed in the world.

https://pastebin.com/2q0ynHHG

Unfortunately there is no good way to fix this issue in FalseTweaks, you need to use a modified version of Project Red and the mods it uses:
MRTJPCore: https://github.com/GTMEGA/MrTJPCore/releases/tag/1.2.1-mega
Forge Multipart: https://github.com/GTMEGA/ForgeMultipart/releases/tag/1.6.2-mega
Project Red: https://github.com/GTMEGA/ProjectRed/releases/tag/5.0.0-mega

Also, remove BetterFPS, it does not improve performance if FalseTweaks is present, because FalseTweaks already optimizes the same code.