Here is the RM600 firmware:-
http://mdl5.mydown.com/driver/200611...mydown1127.rar
(just copy and paste above into address bar rather than clicking on link!)
Try this to get into firmware update mode,
All you do is this,
1) Switch the player OFF using the main on/off switch.
2) Hold down the "MENU" or the "PLAY" button and keep it held down.(try the other buttons if these dont work)
3) Connect the usb to the player.
4) Wait for about 10 seconds before releasing the button.
5) You should be now in "ROCK USB" upgrade mode
6) Then just start ConsumerUpdate and upload your firmware.
btw here is how the battery connects on my player:-
