Update
I went in the dealer in Brussels, they ordered a new one, it arrived and the fitted it the next day - pretty good service all in all.
Interesting thing I learnt in the process, which will make UK taxpayers squeel with pain. They said they sell very few Z4s (despite having a 2.5 roadster AND and M coupe in the showroom, out of a total 7 cars...), because they dont qualify as co. cars. What? I asked. turns out that youca can basically have any saloon as a co. car in Belgium, pay NO tax on it, yes, you did read correctly - NO tax. It gets better. you pay about 100 euros in tax, and you get an UNLIMITED fuel car to cover business mileage and personal.
As I'm the only british expat in a company of 1000 belgians, they all think the streets are paved with gold becuase of the Z4, but they are the ones with the sweet employment package.