Also still having the same problems. Have been back and forth with VSL tech for months and they eventually gave assuming it was a conflict with a (then needed) wifi connection concurrently running.
Have since reconfigured 2 Macs and 1 PC all connected via hub (wifi off) and still problems. iMac slave shows most of the time, PC often not. I have noticed if I boot Logic and open a new project the PC is normally showing, however if I boot Logic straight into a current project then it doesn't. It's incredibly frustrating, but at least I have found the workaround of typing in the PC IP and instance name.
VSL - surely you have had enough of these reports since VEP7 to resolve the issue?
Best
Harry