Now you have over 900MB of source code to dig in.
I would take my sweet time to search for improvements in the infotainment software, put the bloody geographical coordinates up front on the GPS app should I ever need rescue from the Fire Department after getting bogged down in the middle of nowhere (you know, longitude, and latitude), or turning the car's screens in a permanent rear view mirror like Tesla did.
Or, changing the layout of everything. Or putting the whole electrical management of the car in the display, a la Prius. Or teaching the car to email its own telemetry to your personal address every 24hours, like it was black box recorder. (I assume all of these items are available on the car). Whatever tickles your fancy.
There are so many useful things that could be done on that code, and "suggested" over to BMW as "customized improvements".