I'm running into the same old issue that I seem to get every single time that I put together an assembly. When I add a mate that will fully constrain a component, SW gives me an error saying that adding the mate will "overdefine the assembly".
In this case, problems arose when I added Coincident 27 to constrain the "Center Circles" component - before adding it, it'd been=free to move vertically on the plane of the court floor, and now it's just sort of fixed in the arbitrary position that I'd had it in.
Any help would be greatly appreciated - thanks!
P.S. assembly is in a zip folder attached to the post .