Forge: 14.23.4.2705
McJtyLib: 3.0.0
RFTools: 7.50
MouseTweaks: 2.8
Crash Report: https://paste.dimdev.org/raw/olozenehex

The game crashes as soon as you open an Storage Scanner from RFTools. There have been some changes to McJtyLib recently, which likely are the reason for the crash.

Hmm, could you report that to McJtyLib? Maybe they can pinpoint the change that causes this.

Hmm in my GUI class I override isMouseOverSlot() (which I made public with an AT) to detect if my mouse is over a slot and then do something. Seems it is messing up there somehow

The method where it starts (GuiContainer.getSlotAtPosition()) is called by Mouse Tweaks once per frame with the mouse X and Y coords and it seems to be crashing somewhere inside there.

There's a similar crash with some other mods #3 but I haven't looked into it yet.

I'm not exactly sure what is going on but it looks as if you're calling a GuiContainer function before something in my GUI class has had a chance to initialize. But I can fix that on my side by initializing it then. That will fix the null pointer exception and should be fine.

Alright, it's probably the best solution considering every other GuiContainer works fine.

EDIT: unless I'm doing something clearly wrong in which case I'll happily fix it in MT.

Fixed with the next update of McJtyLib.
McJtyMods/McJtyLib#74