My recommendations, based on my experience with this engine, in order of priority.
1.) GLOW PLUG!!!! This engine is married to the OS A3 plug -- I have seen several engines from other club members that were difficult to start and when they switched to the A3 plug all their problems dissappeared.
2.)
I use pure methanol+castor oil mix no nitro
I know your probably not using NITRO because you can't where your at. Try putting a few drops of ARMORALL in your mix. This will reduce the fuel's tendacy to foam.
3.)
don't break-in an ABC type engine too rich or you can screw up the fit between the piston and sleeve.
rcflier_gi is correct here. The OS FX .46 is an ABC engine, it does not have a ringed. You need to break this engine in at a leaner setting than you would with a ringed engine. It has to get hot to get the parts to properly settle in.