Calipers won't retract...do I need a special VW only tool? I bought a simple tool to fit the caliper, rotated the piston (pushed hard..even used gentle C clamp pressure), but no luck....Help!!

Are you turning clockwise as you look at the face of the piston? The rotation has to be done while fairly strong pressure is on the piston, the small cube tools make it difficult to do both operations at the same time. Some auto parts stores like Autozone rent the correct type of tool.