Multi actor pawn / attaching actors w collisions to your Pawn

Hi all.
I’ve been experimenting with custom pawns for some time and this well known one collision - must be root thing is killing me.
My project depends on spawning additional actors as attachable parts for my pawn. So the shape of my pawn is fully
customizable - so it’s shape is also unpreditable. I’ve tried attaching actors - collision does not work for thoose new parts - it works only for original pawn’s collision shape. I’ve also tried to use custom and procedural meshes as collision shapes - after attaching new part to my pawn I do vertex update, then generate mesh around both pawn’s mesh and it’s new part and still no luck - collision works by generating hit events but pawn’s movement is still unaffected - additional parts of my pawn still pass through walls. Help.