Ubisoft installers (SetupUbi) - continously refresh of window

ReactOS 0.4.15-x86-dev (Build 20220930-0.4.15-dev-5125-g23b7c7b) (Commit 23b7c7b8234e48ed35ce7c40ce80a04d43432d3d)
 
Software affected: anyone using Ubi Soft Intaller era 2000-2003 (direct example: Rayman 2 demo https://www.3dfxzone.it/dir/3dfx/utilities/?objid=1131 )
 
Attached video for a quick example: the window is continuously refreshed. It happens both in active and in inactive status. The only moment I found where it stops is when interacting with a nc icon on the titlebar. It resumes when moving the window.
 
(Used Hype: the time quest for the debug log)