creating a collision polygon in 3d max

hey, anybody here can tell me how can I create a model in 3d Studio max with collision polygon? or, how can I find the size of the model to set up a collison solid? can I create a retargular solid for my model instead collision sphere or tube?

What I do, is edit the .egg files and insert tags, and get rid of some redundant tags in the process.
I understand you can use only the collision sphere for the moving objects, for pasive objects you can use any as described in the manual.
The tube works with some collision handlers, but not all.

This actually bugs me, since its hard to setup realistic collisions.