I have also a MDH-10. It is original in box with all including. I am an old fan of MD since I was in Japan in 2000's and have numerous players (incl. a car set) and recorders.
Certainly the EDL MD Studio: Transfer Editor would give great potential to the use of the unit. I guess the modified one works with Windows up to XP as a relative brochure for the software states while the original driver floppies I have are for DOS 3.1 and Win 95.
I am aware that to use it with EDL it may need firmware modification but I would like to give it a try since I am quite familiar with computers. I would appreciate any ideas about that.