For whatever reason i cant seem to get this map working on my swrp server, whenever i spawn i get darkrp table errors but its just this map - the server works fine on any other map. Any idea what might be causing this ? thanks!

no idea.
unsub to map, unsub to all addons. run a dump check. then resub to everything. Steam likes to partially download content all the time.

This map has nothing that effects the DarkRP script, so no idea.

Sometimes when you load into a server with the map, some of the textures are missing (downright invisible) and the only solution we've found is to close out of Gmod, uninstall the map, and then reinstall the map.

No clue if there's a different work around, and the workshopdl for the server should be working otherwise, as this is the only addon with this issue and it rarely happens as is, but when it does, it usually happens for everyone.

thats a steam issue.