The "Windows 10 bug" that caused the game to run in 1-2 fps have finally been fixed!

It's taken an insane amount of time, much due to the aging engines incompatibility and partly a shortage of time on my own part.
There's been a lot of support, help and fixes from the community and after much testing and troubleshooting we finally have a new Launcher that fixes the Windows 10 vs DX9 incompatibility.

Thank you Community for all the troubleshooting and support!
And thank you Markus Hohmann, without your help I'll probably still be walking in circles.