No worries, always more than happy to be able to assist where I can.... Main thing to remember with this and most warbirds is to not come up to fast on throttle during takeoff due to swing to left, if eased on rudder has chance to become fully effectly and will then be a breeze. Also the wingloading is higher than the models you have mentioned there so remember keep the speed up a little on landing approach. A tip stall with flaps deployed likely will be unrecoverable especially if during landing. Maybe good to get use to flaps up high and practice steep aproaches with reduced throttle, I didnot bother mucking around with various settings I just use max deployment approx 40 degree deployed mid to 2/3 down wind and curved steep approach as mentioned, it does not pick up much speed and easy to manage after little practice.

I dont recall CG from memory, but will check within a day or two and let you know as I do have it marked on model Iam sure, its been stored away for quite a few years and during two house moves now.
Re- 4 stroke mufflers I have found that on many 4 strokes the so called 'muffler' does not really offer significant noise reduction and internally some like O.S. and Y.S. have little in way of serious baffeling, they seem more ther for somewhere to attach tank pressure nipple. On my Y.S. I run simply without muffler or pressure nipple due to already pressurized fuel system and just attach a section of brass tube extension clamped to exhaust header nut. On the O.S. with its curved header I just remove muffler and drill/tap end above threaded section to add the same pressure nipple that was on muffler. The noise difference is not significant and infact has a slight bark to it... deffinetely more noise can be heard inflight coming from prop, thats why I go for larger diameter, finer pitch as they make less whine at lower RPM they spin at. I dont have any pics of the O.S. but heres the Y.S. set up the same but in a Acro Sport bipe.

Oh yeah I was meaning to ask why did'nt you mount engine inverted?

Cheers- Marty