In the map, Classic, the zombie man models show up like this for me. I do carry vista so that could be the problem too? I did delete and redownload them. Nothing. This is the dead zombieman you first see when you spawn and go to the door. He looks like crap, eh? The live ones do this when they shoot too. Please reply (if you don't got no idea it's ok not a big deal i just want to know wtf is going on).

You could try to replace then with standard hl models, if these don't work properly.

This could also be from a driver problem too, have you tried different versions of your gfx drivers? maybe an older set of drivers that still supports your card will work better.

I get the same thing, sometimes even worse. Sometimes enemies just disappear right in front of me then reappear, or constantly blink in and out until I guess where they are an manage to kill them.

I use lo def models, and i get that. I am also using Vista, so who knows. idk why but i perfer most lo def models

You can try these, these are the hd models. Extract them to your classic models folder.