Hi!
Too much nitro will present the sympthoms you tell us! -Impossible to set at full throttle!
Second You have to use a silencer/muffler on the engine! Other vise you cannot pressurize the tank (which you must do).
Third...Use a 11x6 or 12x6 APC prop! 10x6 is a little too small prop for it.
Fourth...Use an Enya 3 or OS 8 glow plug.
Fifth ...The MDS engines are made to run on low nitro fuel. Use 20" Castor oil or 20% all synthetic oil or a mix of the two and max 5% nitro.
No running in is needed in any modern glow engine as all modern engine are either ABN, AAC och ABC made. The only thing you have to do is set the tank properly, center of the tank inline with carb orifice and as close to the engine as possible...and of course set the needle (at full throttle) a little rich and run the engine with rpm altering between a little rich four stroking and clean two stroking...but not slobbering rich!