NVM its the same thing with only a few differences...sorry

New Stable 1.1.87

1.085 Error ModManager.cpp:1623: Failed to load mod "SchallTankPlatoon": SchallTankPlatoon/prototypes/gun.lua:18: attempt to index field '?' (a nil value)
stack traceback:
SchallTankPlatoon/prototypes/gun.lua:18: in main chunk
[C]: in function 'require'
SchallTankPlatoon/data.lua:3: in main chunk
1.086 Loading mod core 0.0.0 (data.lua)
1.133 Checksum for core: 2010374811
1.169 Error ModManager.cpp:1623: Error in assignID: recipe-category with name 'crafting' does not exist.

Workaround: Remove the line 18 in the gun.lua:
tankAC.attack_parameters.sound[1].volume = 0.5 --1.0

The game will load again.

Edit: Not sure what effect it will cause to the volume

tried that, didnt work sadly

Sorry for the late reply.
Have not expected a game minor stable update would break my mod. Thought the game is still on 1.1 and my mods would still work fine...
So I assumed being safe to take a long break from Factorio.

Anyway, found out 1.1.83 has changed the prototype definition of tank cannon firing sound. It added an extra dimension to the array, rendered a simple array indexing failed to work.
I have applied additional checks to recent mod version 1.1.2, which should now be able to handle both pre- & post- 1.1.83 game versions.