This is how to do it:
Updating the firmware of your DwarfConnection Wireless system is easy and can be done right from your own PC*:
Connect your transmitter or receiver to your computer using the USB port. Do not forget the power supply!
Press and hold MENU on your transmitter or + on your receiver while turning it on.
The device will show in the explorer.
Now copy the latest firmware file to the device and you are good to go!
* Yes, it HAS to be a PC...