you have to take into consideration, that the normal behavior of the dash lights is as follow: on when lights are off, dimmed when lights are on.
this is the late 2010 EU model.
so probably the dimming module is at fault.
there is no rheostat in this model and I don't know if you can add one.
as I have the early 2010 EU model, I added a rheostat and it works like charm.
I would guess that the dimming module located behind the blank panel by the ESP button.
I also would guess that the immobilizer keypad is located over the blank panel. so probably one of the screws holding the keypad did some damage.
in Israel, the anti theft insurance is valid only if you add an external immobilizer. and guess where they put the keypad for the immobilizer? they screw it to the blank panel of the dimmer.