does the collision in blender have to have a specific name or anything else like that?
or can i just save the mesh as a dts and have it work (which i have done)
it has to be named like col-1 or col-100 or something prefixed with col-1 ie col-105
and it has to be convex, if your shape is convex (which your shape appears to be) then you need to split them into different meshes
so you would do your cone at the top as one mesh ie col-100 and then the base part of the brick as another mesh ie col-101
then export as a dts and referr your brick datablock to that dts as its collisionShapeName