I made a custom msh to be used as an "autoturret" as far as the game knows, but when I place it it falls through objects, terrain, everything. switching only the msh to the original dropturret seems to fix it. So what needs to go into a static MshEx'ed model to not fall through?

I tried the stock detpack msh also. It also falls through.

how did you call your collisionobject?

i dont have one. just the geometry. doesn't mshex add collision? or would mshex keep collision primitives?

The same msh did work for a walker.

mshex doesnt keep collisionprimitives but normal collisionmodels. make a cylinder/box standing on the ground and call it "collision_-t-whatever" and another kmore precise collisionmodel called "collsion" and see what happens ingame.