I find it hard to believe they had the bike for so long and can tell you there is nothing wrong with it and then it won't idle at all from moment 1. There is something a miss here ? Find an independent performance motorcycle tuner. They will be able to advise on where you can find an aftermarket CPU. I know this engine is a new Chinese version of the Rotex motor and there have been some lemons. However BMW in Aust. fixed them (see previous posts). There are a few 650 thumpers on the market so there must be a cpu that will have some adjustable mapping options so you can at the very least get the thing to idle.
Alternately call the BMW importer and tell them you are about to run a full page ad etc. They may put you onto another dealer who has a mechanic with a bigger brain.