Door activated courtesy lights

I bought a 2007 Kia Sorrento 3.3 4 weeks ago.

I have had quite a few issues, not with the car, but with the dealer.

The one thing unresolved is. I had the roof DVD fitted as part of the deal. When I received the car back, the courtesy lights built into the DVD unit will not work off the doors, only off the built in switch. The boot/trunk light is now the same.

When I spoke to the dealer, he said that was how it is supposed to be.

I just can't believe that and the DVD handbook clearly states that the doors should activate the interior lights.

Can you advise what is the true story?

Thanks

John