It's been several years since my last rally, but the previous ones I attended included several tech sessions where items of special interest were discussed. I didn't see a tech session committee listed on the rally site. If there is one, I have 2 topics to suggest that might be of interest.
1. A review of drive shaft and final drive construction and maintenance. Include fluid changes, spline lubrication, 1-piece vs. 2-piece drive shafts, and failure symptoms.
2. A discussion of how the ZFE controls the accessory and GPS sockets. This should include a review of the ZFE logic for determining when a socket remains "hot" after the ignition is turned OFF.
Both topics might require the assistance of BMW NA technical folks.