Tree MESH collider issue with prefabs.

I have looked all around and the unity staff and mods never seem to answer this question.
I know the standard way people like to give trees colliders is to create a capsule collider and generally try to get it to fit the shape of the tree, but thats just not good enough for the FPS I am currently developing. I need it to be form fitted, therefore I am looking for a solution to my dilemma. Placing a mesh collider on a tree itself works fine, but when you place it on a tree then import that tree over to the mass placing tool in the terrain editor it disappears and suddenly you can walk through the trees. I have seen multiple threads mentioning this but no one has given anyone a concrete answer!

 

It's been a some time since I worked with the terrain tool, but I think you have to make the tree and the mesh collider into a prefab and then you should be able to use that prefab in the terrain tool.

 

Yes that is what I am talking about, once you put a mesh colider onto the tree and you put it into a prefab it dissapears.

 

Regards, i have the same problem as here. Why is so ??

Steps:
1. take tree place it on map.
2. Add mesh collider
3. Check that on that tree you can't go as ghost
4. make from that a prefab
5. On Terrain tool select that prefab
6. make some trees
7. Still you go through that tress like ghost


Whyyy ? ?!


Selected "Convex" on pre-fab still doesn't work..