There is nothing with the c_trace instruction

I think it is the model itself. Actually, that's a weird model. I had to set the c_move RELATIVE vector to negative values all the time to make it move FORWARD

You can download that model here and check it: http://www.hellupload.com/az5moo4glpdo/ogre.MDL.html

@Malice That is only a 7 MB .mdl model. You can download it.

Thank you all for introducing help