@tago Thorsten released the Windows toolchain - and it is working, just accessing the 64KB extra memory region of STM32F4 will crash the app, maybe it is a simple linker setting, but i investigated a while back and found no easy solution.
On top, under windows, USB MIDI transfers are often very unstable, i.e. when flashing new firmware releases when developing you often have to either rescan MIDI ports or restart MIOS Studio for continuous uploads, which is really frustrating when developing. That is not necessary on a Mac, so you know my recommendation - you can get a used macbook air for ~300€ - while it's not as fast as an M1, it will do the job - imho for that price, it's not worth trying to improve the windows situation with the upper 64kb block, as the Windows USB stability situation cannot be fixed by us.
Many greets,
Peter