OK, I think I've worked out my ProATC-x issue.
When using ProATC-x I found that the zero key to bring up the ProATC-x window inside flyinside works fine for a while, sometimes upto 30 minutes, but most of the time 5-10 minutes. After which ProATC-x continues to run, but the zero key no longer brings up the window in VR. Instead the zero key just brings up a zero in the FMC window.
Finally after doing some flights without real world weather, I found the problem, it only happens if Active Sky 16 is running. If ActiveSky16 is not running ProATC-x window importing into VR works fine the entire flight.
Is anyone else having this strange problem???