Hi all, I found a workaround for Windows 7.
First I loaded an older version 23.6.3 from Itch (published 2018-05-01) via that link:
https://www.filehorse.com/download-itch-desktop/34938/download/
That starts on Windows 7 and it's possible to download and install apps.
By the way I have to rename the program.exe file to program.app in
C:\Users\<username>\AppData\Roaming\itch\apps\<game> to get no ENOENT error during the start.
Good luck!