Blender: How to create a collision properly?

[opti2000]

Hi all i got a little problem. I recently started to work with blender and got my model here now but if i compile it and make it source compatible it shows me the collision model
like this in hammer.

[IMG]http://abload.de/img/unbenanntklu8h.png[/IMG]

I am still a newb in this and i tried several (possible) solutions. I simply cant find any good tutorials to create a collision model for source models. Anyone can help me?
If you wanna see my QC file here it is but i think everything is fine with it.

$modelname	"Opti\crucifix.mdl"
$scale 26
$body mybody	"crucifix"
$staticprop
$surfaceprop	wood 
$cdmaterials	"Opti"

$sequence idle	"crucifix"
$collisionmodel	"crucifix.smd" { $concave }

[opti2000]

#closerequest

Found myself out how to create perfect collision models