In the bootlid both sides...what are these two panels? Almost look like some kind of piece to use to seal off the corners when the roof is down...like mini tonneaus?
Not so far! I haven't had the car long and apart from driving it home have only driven it one other time which was last weekend to the Peak District.
I'm laughing because I'm also a member on a BMW Z4 forum. I still have a Z4M and an Alpina Roadster S plus I actually sold my Z4 3.0Si to buy the R230. On the Z4 similar things are available as a fairly rare optional extra (but you have to get out of the car to screw them into place).
There's a thread currently running on that forum about the stupid amounts of money people will pay for a second-hand pair of these accessories. They seem to go for up to £300 in the UK and a set recently sold on Ebay in the USA for $450! And, they literally are just two pieces of plastic. They don't even have the rubber seal that these Mercedes ones have!
The roof on the R230 is pretty complex as you will see when you eventually lower it. Multiple switches control each part of the operation and if any one switch fails to operate at the correct time the roof will stop. My advise is to operate the roof and make sure it works correctly and if it does don't mess with it.
I only lowered and raised it to check it was ok when I was buying the car. I haven't moved it since as it's been in my garage with me detailing it since apart from one drive at the weekend the the Peak District and the weather wasn't right for opening the roof.
I might take it out of the garage and open it tomorrow as I want to get to and treat the rubber seals that I haven't done yet.