I have win 10 64 bit machine with V5 and other arturia plug ins that worked.
Today I purchased the V6 collection. It registered fine but would not authorize (also downloaded the latest ASC)
different responses each time, could not contact the software agent, could not sync licenses, also my other plugs stopped working.
I tried re-installing ASC several times same issue with no response. I finally noticed that when I tried to authorize , the ASC agent would turn from a running state to a suspended state. This was causing my activation and licensing issues.
On a lark I changed the properties of the agent to be compatible with windows 7(after trying other settings) and VOILA! V6 authorized, and my other plug came back to life.