FSE 450 2005 idle misfire/stall when hot

[Tafka]

Okay...i'm out of ideas.
I have a 2005 FSE450, last year rebuild, new crankshaft,piston,cylinder etc.
At one point, this year, in the middle of the forest, bike started to idle rough(misfire) and then stalls. Starts most of the time easy again and runs a little bit but then again, idle/low revs misfire and stalls if not given throttle.
High revs, everything OK. Some backfire when slowing down. Works fine when cold! but about 20-30min riding, engine getting hot, then the issues start.
Can't ride properly because stalls too often when riding slow forest trails.
Changed and adjusted TPS, new fuel pump, water temp. sensor, checked air temp sensor, fuel injector tested-good spray pattern, no leaks and flow rate ok.
Can't find any air leaks.
My next step would be change:
1) Ignition coil - i think i can find VW analogue (hell no i'm paying $200 GasGas "original" coil if i can get VW coil with $25)
2) Fuel pressure regulator? - PITA to find in Estonia :/
3) Pick-up coil? - does anyone know what should be the gap between pick-up coil and toothed wheel?

Any ideas?