I switched to the latest version recently and unfortunately, I had some issues with it.
First of all, I had the same problem as @Lemot. I have default skin though.
My initial thought was to close FL and reboot the PC.
After the reboot, my PC stuck on the Windows loading screen, and eventually gave me this error:
Somehow, after several attempts to fix the situation I managed to boot Windows 10 back (I won’t go into details, one thing that I did not use USB or whatever).
I decided then to delete Vital 1.5.5, clean the cache, reinstall all my drivers, and rebooted.
Installed Vital 1.5.5 once more - a couple of days everything was fine and now it just freezes and crashes upon opening, both standalone and in FL.
I can not open presets made in 1.5.5 in the oldest version of Vital.
Any ideas on how to fix it?