I had the Piston for a while before I sold it to Brent. It was a great knife. The pocket clip screws go into threaded inserts. These are the same inserts you'll find on the Echelon for the clip screws. They are also used for body screws on knives like the Skyline and Echelon, and of course the Piston. When you see body screws going into G10, look where they go and you'll find these inserts. They're very strong, and are indeed steel.
In terms of the thumb studs, you can't easily move them. They're press fit into the blade. I'm not sure why you would, as they are directed perfectly to facilitate a good deployment with the thumb. If their orientation isn't comfortable, then it's my opinion that you modify your technique a bit, as I've found the studs are a great guide for directing the force.