Pilot reported loss of engine thrust during a take off on a post maintenance flight. The pilot returned to landing at departure airport.

Narrative

While Conducting a post maintenance flight on a DA42 I experienced a loss of power on the Right engine at 200 feet AGL after my initial take off climb. At first it was reduced to only 75% then gradually reduced to zero thrust. The engine however was still running and produced either zero drag or minimal thrust. Subsequently there was an observed glow coming from the engine nacelle and sparks coming out of the engine nacelle as well. I shut down the engine and performed a single engine pattern. A landing was made with no damage to the aircraft or injuries. After landing there was observed smoke coming out of the engine but no fire. I have a-lot of experience in DA42NG (200+ hours) but limited in the Thielhart engine equipped Diamonds. I have only ever heard of or had problems from these engines. The Austro engines on the other hand seem to be more reliable. I believe that the Thielhart engines should be investigated for their longevity. I do not know what caused the problem but it is possible it was the result of a turbo fire.