Upgrades on a barrel - tier iron, gold, diamond and pickup.

https://pastebin.com/kdQzk7pX

Caused by newer forge verision. Welp

What version of Forge does Yabba support?

I think 14.23.1.2556 still worked. The changelog says

Build 1.12.2-14.23.1.2558:
	LexManos: Re-enable Vanilla's Shapeless recipe matching.
	LexManos: Restore binary compatibility in EntityItemPickupEvent

but I guess that's not true for Yabba

Thank you. Any updates coming soon?

Holding back updates for now, because Im doing large rewrites in all mods

I had this crash as well when I had a YABBA barrel (with the pick-up upgrade and 1 cobblestone inside) in my inventory. I tried to walk over a cobblestone item drop in the world when the crash occurred.

I'm running:
FTB Revolution v1.3
YABBA v1.0.11
Forge v14.32.1.2587
Minecraft v1.12.2

Here's the crash log:
crash-2018-02-04_23.05.17-server.txt

Hope this helps.