A-800PRO not receiving control map

Hello, new user here.
 
I recently bought a Roland A-800PRO, and I would like to use it to change patches on a Roland XV-2020. I thought of assigning "Bank Select + Program Change" to the pads, so I used the A-PRO Editor to create a control map for that, named "XV-2020". I made just a couple of assignments for testing. Here's the info from the Parameter List page:
 
A1 | Ac. Piano | PROGRAM CHANGE | Bank: 93/ 24(5D/18) PC: 1(00)
A2 | Pop Piano | PROGRAM CHANGE | Bank: 87/ 64(57/40) PC: 5(04)
 
Then I selected Control Map 19 from the drop-down, hit "Transmit", and confirmed. A progress bar appeared after that, no error message. At the same time, the display on the A-800PRO read "Receiving..." and returned to the normal Control Map screen. After all this, when I select Control Map 19, it reads "NO ASSIGN", and the pads don't do anything. That means the Control Map wasn't saved on the controller.
I scrolled through all the control maps, thinking it was saved somewhere else, but no success. Tried re-installing the driver (I'm on Windows 10), doing a factory reset on the A-800PRO, changing USB ports, changing the MIDI I/F Switch parameter, changing the Advanced Driver parameter, and the result is the same. I did a search on Google, nothing of the sort came up. So I registered here only to ask if someone can help, cause I honestly don't know what else to do.
 
Best wishes,
 
Flavio.