Win 10.
VST3 version of Limitless 1.05
However, I found a workaround! Cannot believe I hadn’t tried this before. The problem in WL is obviously a GUI redrawing issue (or whatever it’s called):
Press the DMGaudio logo to see version number and setup. Voila - the GUI redraws correctly when closing that popup window.
So from being a major problem, this is now just a matter of two mouse clicks. Can live with that.