FWIW …
My transition from iLoks to Plugin Alliance did not go at all well.
Aside from initial licensing errors … which support overcame after a few days … the ‘new’ version does not load the previous version’s settings. This happens even if those setting were separately saved … meaning separate to the master section pre set. So, I don’t think this looks like a WL issue … the plug won’t load it’s own setting that it created in its previous version.
Now for one VST2 plug … which became VST3 … I kind of understand that and because I had the previous iLok version still loaded I could re-create the settings.
But the other plug was the plug in’s author’s/PA issue I believe. I really don’t see how the host program (WL) can deal with this.
BTW, ProTools does not use VST.