According to the release documentation https://github.com/solvespace/solvespace/blob/master/CHANGELOG.md from Version 3 on the problems with Dot versus Comma input via the numpad on the Keyboard should have bin solved.
It says "The numpad decimal separator key is bound to "." regardless of locale."

I have got Version 3.1~70bde63c. installed.
Does anybody know why it is still a problem for me?