I did something like that on my M3.
http://hometown.aol.com/hyperm3/Dooropener.html
If anyone wants another way of doing it.
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13 HD FatBob
17 A4 Glacier/Black 1st Edition/Pre+/Sport/EurocodeTMD/Racechip
16 S6 (gone),14 S6 (gone),14 S6 (gone),13 S6 (gone),10 S4 (gone)
07 335i(gone)