try these steps on the SG Mod
Best way to get Steam to force download mods:
- Unsubscribe from the broken mod.
- Confirm all files related to the broken mod are deleted. If not, delete them yourself. Workshop mods can usually be found here (depending on your setup): D:\Program Files (x86)\Steam\steamapps\common\Arma 3\!Workshop
- Close Steam and make sure all launchers are closed.
- Open Steam and Subscribe to the mod again and let it download.
this is a direct download to the sg mod also, you can try put that into your arma mods folder directly