hello,
thanks for your posting. We have allready tuned many 1.9 TDI's with the 105hp engine. There is no riks for the car since we do not tune to the maximum power possible to keep tolerances to the engine and turbo. It is important to keep the services and "standard" rules which you also should do with the stock power. (like waiting for the operating temperature before giving full power..)
At diagnostic works at your dealer the car behaves neutraly, and the power increas is not shown on the diagnostic tool.
regards
Ali