working on a polymer 80 compact build and everything seems to be functioning fine. I have notice a slight amount of slide stop movement when I pull the trigger without a magazine inserted. Does this seem right?
Does the gun work? Not sure why you'd see slide stop movement, but I have no idea how much "slight" is and I don't have the gun in hand. Depending on how well you fit the parts, it's probably fine. Especially if you don't notice movement with a magazine inserted.
The slide release should not move when you pull the trigger on a Polymer80 frame.
To insure the slide release is properly installed, remove the slide and raise it up. When you let go, it should spring back into place without resistance. If it does not return freely, check to be sure the end of the spring is under the top pin and not over it.
I had problems with one and found some burrs inside the pivot hole were making it a little slow to return. Cleaned the burrs and it works as it should. Took me a while to figure it out because I did have it assembled correctly but it never worked smoothly.