@JonasTMT consider checking if meshculling is set to =1 (enabled) or =0 (disabled), inside the main level file (the main.level file or whatever it's called). You can use notepad++ to bulkreplace meshculling=0 to meshculling=1
Would removing the un-accessible parking towers cause less lag and swapping the petrol stations with the standard ones work?
i7 6700k, gtx 1070, and this map lag's like HELL. that is the only mayor problem to this map tho, so if it could be fixed, that'd be great