I think I nailed the bastard. It's definitely the type of shader related. Today I was tweaking aircraftsmokeeffect for MigAlley proposed effectspack, and in this effect has in it dark cloud of smoke similar to flak one but smaller at start of smoketrail emission. The new emitter uses "standard" smoke texture, and as such uses effectLightLevel.fx shader. And it didn't show up (man I blasted dozen MIGs in the testing process without any luck) until I changed aliased shader to effectFire.fx, voila, works like a charm! BUT to make things more confusing many other effects/materials have the effectLightLevel.fx shader applied AND show just fine..?
I guess it has something to do with particlesystem.ini references -some effects that don't use new materials (effect material defines particle .tga graphics, type of shader applied and type of particle vs. particle blending method among other less important things) and don't have new ones defined in their ini files, go back to particlesystem.ini and read materials descriptions from there. I must look into particlesystem... segment by segment, even line by line