From my experience, adding options never lowers a payment on a BMW lease. In nearly every case I've seen, extra options always equals higher monthly payment. One of the few cases that I can recall in recent memory where a more expensive car was cheaper to lease was my parent's X3-- in 2004, BMW charged extra for a moonroof and auto trans on the 3.0, so the MSRP included $1275 and $1350 for these items. When they got the car, I was able to get a special incentive from BMW which basically made those options "free" by reducing the selling price, but the residual was still based on the higher MSRP.
As for accessories, BMW does allow partial residualization for some options, including (but not limited to) CD changers, aerodynamic kits (you have the get the entire kit, not just part of it), accessory hard tops on convertibles, running boards on SAVs, etc.
Dealer-installed accessories, such as alarms, Lojack, paint sealants, warranties, etc. are not residualizable.