I have one of these. I don't think I took any photos of the insides though.
If you put up some photos I might be able to point you around the battery and power supply area.
I will open the unit and post some photos shortly.
Or is your battery just dead? You should be able to measure some voltage at the battery connector.
The positive terminal is next to the notch that is cut out and negative on the outter edge. Perhaps try and manually charge it with a 500ma 12v supply for a while and monitor it.
The battery is OK. Altough it does not get charged by the unit itfself, I charged it outside and it is fully charged. The funny thing is, as soon as I input the battery into the unit, it powers on by itself.
And its not possible to switch it off. The button has no effect. I have to take the battery out, to shut it down completly.
For option 21, seeing as it is not coming up in your option list when booting then perhaps it is not installed? Or the eeprom was corrupted? Is it just a software unlock of the already existing hardware?
hmm, i not 100% sure that it needs to display at the startup. It just found it odd, that Option 3 is display, but not 21.
When you go into the "Modes" screen. What do you see?
Thanks alot already!