whats with the charging issue ?
did you flash the phone ?
if so did you flash emmc too ?
san you connect the phone to pc via usb cable in mass storage mode and transfer files ?
what exactly you are using to charge the battries inside your n900 i.e the normal way via a wall outlet ? model of the charger or better is it 1amps ?
lastly observe the notification led while you plug in a charger and tell us the pattern also do you have acces to a multimeter as you comfortably put to use crocodile clips to charge your battries externally.

All this to diagonise your charging problem precisely .
answer them in sequence.
thanks