When you say 'the back-up copy will be loaded' what do you mean?
There are two copies of all the model data (model number, calibration data, etc): the working copy and the backup copy. I can't say for certain whether the model number has been changed in both copies (for those of you who can't get it back), but in any case, this method, if successful, will restore the backup copy.
Once the scope is booted and the 'help' button pressed.. What next as regards FW?.. Do you mean just re-install FW01.01.00.02 or press a sequence of buttons to reload some saved FW?
Re-install
any FW - if you have gotten to this step (i.e. invoked the firmware upgrade bug by causing it to freeze while upgrading) you can use any version of the FW (00.01.00.05, 01.00.00.03, or 01.01.00.02) because the DSO should automatically use the backup copy of model data while upgrading:
The boot loader upgrade method:
1) Use two hands when booting up - one thumb on the 'Power On' switch - one thumb on the 'Help' button. When you press 'Power On', all of the scope LEDs will light for ONE SECOND - during that brief period, you must
PRESS AND LET GO of the 'Help' button. It can be a little tricky, but when it works, bootup will stop before the Rigol logo with the 'SINGLE' button lit (if it doesn't, turn off power and try again until you get it).
2) Then insert the USB stick with whatever FW file you want to use on it. The CH1 LED will start to flash as the DSO loads the file.
3) Once updating is finished, several of the LEDs will light up - and all flashing, etc. will stop.
4) Remove the USB stick and reboot, and check your model number.