As far as one can tell you run the exe and rename the inf file created in the WINNT/inf/ folder to a name of your choosing. Then edit the line
specifically toCode:%Test.DeviceDesc% = Test_MTP, USB\VID_xxxx&PID_yyyy
for the MP3 player in question.Code:%Test.DeviceDesc% = Test_MTP, USB\VID_04E8&PID_5081
Then point the driver installation to your renamed inf file.