Ok then, thanks for clarifying the 'overcharge' issue.

I shall wait for a while now, I´m going to be busy during next days, anyway, and I would try any of the new codes that might appear in this thread.

Also, bearing in mind what you told me, I´ll try to monitor the charging rate in a proper way just to check whether is just reasonable or too fast as previously afraid.

As for the MicroUsb connector modding alternative, I have found a Qi receiver that seems to have the full FIVE pins in the MicroUSB head itself, but your never know with photos featured in those Chinese e-Shops. It seems that shortening pins 2 an three could be done somehow. Although the ribbon is placed in the center of the unit, it seems long enough to be folded in a sort of "Z" shape in order to clear the N900's camera area.
Another advantage of this unit, it's the fact that it provides an output current of 1000 mAh, which doubles the 500 mAh of my current Qi receiver. Should be that useful for a quicker charger process? (which I'm not sure of being diying for...)

Anyway, I'll leave by now, And I´ll wait in order to see whether you and Pali comes here with a nice code that allows me to keep what I've got.

Thanks again for your all your kind help.