This is what I get on startup:

Error loading mods

Failed to load mods: MushroomCloud/prototypes/ground_zero.lua:256:attempt to index field 'action' (a nil value)
stack traceback:
MushroomCloud_/prototypes/ground_zero.lua:256: in main chunk
[C]: in function 'require'
__MushroomCloud/data-updates.lua:3: in main chunk

Mods to be disabled:
MushroomCloud(1.0.17)

i confirm it doesnt not work with rampant arsenal

Thanks for the report, I'll look into this.

thank you this you mod is a must

Rampant arsenal just got an update and mushroom cloud works again !

Excellent. This means the bug was not caused by Mushroom Cloud. Phew...