I've found one great problem. at first fullbright object models haven't to be effected by "model lighting" option.
And the second: when this option is "On", png model skins with partially translucent parts are drawen with great bugs - not only colour texture becomes darker on some model angles, but it's mask too! and so we get that for example muzzle flashes sometimes are not visible, or visible but too translucent and dark.. Can it be fixed? just not to effect vertex lighting to fullbright objects or model parts.. i think so