Sil-Glyde might be a good alternative lubricant.
It was recommended as a non-hardening, plastic friendly lubricant on a Full Size Jeep website. It was specified in a DIY to lubricate replacement plastic flex-track for old Grand Wagoneer "Woody" power windows. When I replaced the flex track, I also removed the hardened lithium grease from the power lock mechanism and applied the Sil-Glyde. Both the power window and door locks have been working well for 2 years.
2013 535i - ED, Oct 2012 | Cashmere Silver | Oyster/Black Nappa Anthracite | ZCW | Sirius | Air Blue 80
2008 X3 | Monaco | Sand/Black Light Poplar | ZAP | ZPP | ZCW | Xenon | Rear Fog
1988 Grand Wagoneer | Burgundy | Ghost Flames | 360 ci | Holley carb
BMW CCA #422951