Sorry to be here again asking for help, but I tried installing the driver on every computer I have access to, and even using every USB cable I have lying around, to no success.
Is there at least a way to revert to the original firmware rom? I had no problem with that, and even with no doubts worse than the Legacy Rom I can't use the GPD Q9 at the moment.
Actually, I had no problems that I remeber until I dediced to enable the "memory swap" option. The setting that enabled faking the SD card as the internal one.
From that moment on, 1) many games keep downloading their data as if they are not installed, 2) some games complain that they can not be installed on the external storage and, most important to me, 3) Retroarch completely stopped working!!!
Every time I launch it it downloads it's assets again (seems related to point 1 above). If I try to launch any game in my collection (they are clean and thoroughly tested and they work on the sama version of Retroarch on my PC) Retroarch crashes.
I even installed a log debugger to look into the problems and the error message is that the Retroarch cores are all missing, even if I installed them, so it really seems that the "memory swap" switch screwed something in my GPD...