Collision problem


Sorry for my english I’m a french newbie …

I’m using coppercube ( and I tried
to see what Unreal 4 can also do for me …

I use to import complex static mesh (.obj) (a kind of castle) I built with 3DSMAX.
With coppercube collisions, using a third person camera, there is nothing
to do and it works immediately without any problem for me.

I thought it will be the same with Unreal but not. It seems
Unreal have to built a complex collision map or else using
convex hulls etc.

I’m very surprised. Coppercube is a small software compared to
Unreal. What is Unreal’s problem with collision ?