I tried that too. I can go through the objects. I wanted to have that mansion road, but the problem is, I can go through it.
As i said it is ported from GTA:SA so i guess the .dff has its own collision, and you can useinstead of
<collision type="autogenerate" />
<collision path="none" />
@KAKAN please can you explain what is not working ill be happy to solve your problem but first try enabling debuglog and see what is the exact problem, i will generate the collision and update the link tonight