I fabricated my rear panel from a piece of sheet metal and covered it with vinyl. My local BMW auto dealer gave me a couple of adhesive BMW Roundels. I think they are for center caps on rims.
I made an led light harness to plug into the factory barrel to keep the “Bulb Out Fault” from coming on. But, like op says, it comes on and goes out every time you hit the brakes.
Jesse Kriner - Hope Mills, NC
2018 Grand America - Black Storm Metallic
14 GTL, 05 LT, 85 K100RS