The game was crashed on load with the following error & logs

Failed to load mods: OCs_base_assets/prototypes/utils/recipe-generator.lua:433: attempt to concatenate local 'result_amount' (a nil value)
stack traceback:
OCs_base_assets/prototypes/utils/recipe-generator.lua:433: in function 'resolve_materials'
OCs_base_assets/prototypes/utils/recipe-generator.lua:447: in function 'resolve_materials'
OCs_base_assets/prototypes/utils/recipe-generator.lua:576: in function 'recipe_transformer'
OCs_base_assets/prototypes/utils/recipe-generator.lua:669: in function 'single_recipe_generator'
OCs_base_assets/prototypes/utils/recipe-generator.lua:768: in function 'batch_generator'
...ting__/prototypes/compatibilty/aai-vehicles-ironclad.lua:11: in main chunk
[C]: in function 'require'
OCs_ammo_casting/data-updates.lua:12: in main chunk

https://1drv.ms/f/c/e1120e79b63ebbbb/IgDMVi7qTDqXTqfslUipzzNsAT_mcL7QFDM3jSSERTI8Hy4?e=bNUfgt

I still work on a fix but it is hard as I cannot reproduce the bug myself. Could you test if it works without the aai-vehicles-ironclad mod? If so, then the error is much narrower, I hope.

I couldn't. Some of the mods require Ironclad mod to play

I don't ask that you play with it, I just want to know if it still causes the same issue. Furthermore, as you mention that other mods require the ironclad mod, which one is it? maybe it messes the ironclad recipes in a way such that my modo breaks.

Got it, will check soon

Checked
The mod that required ironclad is "Planet Virentis" and "Combat Tweak and Additions"
and after I disable them (ironclad and two mods above) and re-download your mod, still got the same crash

Thanks so far, I will give it a deeper look in the evening.