dose any one know the code for atatching smoke to come off something.

I assume that you are talking about the smoke that comes off the mg42 when it overheats. As far as I can tell, the smoke is coded directly to the gun, and can't be changed using the qc.

This is apparent when you try to replace the default mg42 with a custom model from 1.0, it still smokes when you overheat despite the fact that there is no code calling it in the qc file.