How to fix the infamous 406 CVT transmission problems?

I've got a 2008 Peugeot 308 with the infamous 406 CVT transmission which has been giving me constant headaches. The car has only done 80k miles and I'm getting error codes indicating a faulty sensor, but the dealer just shrugged it off saying it's a design flaw! Has anyone else had similar experiences or found a solution to this problem?