IL2 1946 4.13.4m Stock.
It seems that the SetPaint command line used in the timetable.dcg file to choose a squadron non-default skin don't works.
From my timetable.dcg file:
19410102 SetPaint III_KG100a1 = vp_festung.bmp
From my Third Party Campaign squadrons.dcg file:
Active False AI Only