Hi, @Eden i am having the same issue, i installed Liberty city mod, it works well, but the addon cars textures look weird, how did you solved it.

The "old" DLC vehicles like bikers, mpbattle, gunrunning, they don t despawn anymore. The problem now is the "arena wars" vehicles, you can spawn it with simple trainer, but if you put them in popgroups.ymt to make them spawn in traffic or try spawning them parked, it will not work, they don t spawn.