Maybe worth a try and check how many current intensity is going from battery when ALL switches and receivers are OFF?
Put your keys off from ignition barrell, close the doors, turn off all switches and dissconect negative lead from batterry.
Then take a multimeter and check how many Ampers or miliAmpers is going between "-" terminal and disconnected cables. Take a lead "-" from multimeter to "-" terminal on batterry, and lead "+" from multimeter to the leads disconnected from batterry.
What You see on display?
Maybe have You any short circuit at instalation or any dimmer / relay is broken?
I have had this symphtom on Escos, when inner light relay was broken. This small unit draw current all time, and after a day my battery was flat.
cheers
maciek