RCU Forums - GGT15 Mixture Screw Initial Setting

Hi, a complete newb to gas engines here, coming over from the electric flight side of the hobby. I have purchased a GGT15 and installed it on a Kyosho Calmato D low wing trainer. I have not been happy with how the engine runs, seems to be losing power after flying for a bit (I have about 10 hours on the engine) and I am concerned that it is running lean. I live in a foreign country and even though I can speak some of the native language I don't have a great commend of it. The people who fly at the club with me a great and very helpful, but I think in this instance they have been trying to set the mixture on the engine as if it was a nitro engine and not as per the manual. So I want to go back to original settings on the carb and just do it myself. This is where the problem starts, The manual states as Step 1 in restoring the Mixture Control Valve to the original setting I need to "Open the mixture control valve (MCV) one turn (360 degrees)". But open one turn from where? If the throttle is open and I try to close the MCV all the way it simply runs out of thread and fully screws into the venturi. Obviously it cannot be open 360 degrees from fully open, so from where is the MCV opened 1 turn from? I have at the moment assumed that I close the throttle body fully and hold it firmly in that position, then screw the MCV in until I feel hard resistance on the MCV with the screw driver. From that position I screw it out 1 turn as per instructions?. For the life of me though, when I do this and then follow the other steps I do not feel any resistance when opening from fully closed, This thing is really well machined and is SMOOTH, but I again am assuming that they mean it is sticking a little bit at the closed position. I get the feeling there is a taper in this assembly somewhere and that I am trying o find a position on this taper where everything is tight at fully closed but will still allow fuel to flow when opened slightly. I hope to get this engine running smoothly and for when I do I have learnt how to tell my friends thank you for your offer of help but leave my damn engine alone!
Thanks in advance for any advice or pointers you can provide.