Make sure that the PlugIns are in the correct folder.
Thanks for the well-intended help, but I checked all that - the plugins show up in the menus and everything, they just behave as if they weren't licenced when in fact my dongle says they are. But I guess from some of the other people's responses that this is indeed some syncrosft issue - sigh. I'll just trust VSL to reset all the demo licences when the issue is resolved (wink, wink) 😊
It's not like I desperatey need them, I have a zillion plugins. But I was interested in the VSL-specific settings, and of course I'm not going to dish out 400 euros for software I know nothing about.