A few days ago i also contacted my supplier and he tried to help.
All i got until now: 2 hex-files and the advice to put the file(s) on a fat formatted micro sd-card in the root directory. I tried this, but using the installed bootloader firmware i think it is not possible to update the device by using an sd-card. The file has to be copied on the virtual disk drive and installed from there as .rdy file.
I think the hex file has to be different. Instead of an app and a sys- file we need the files similar to the DSO-Quad files.