A few questions about effects

Hi all,A have a few questions about effects:1) I'm trying to make an effect of 4 lights in a row. For some reason the X Offset is ignored when I place this effect in my scenery, but when I test the same effect by putting it on an aircraft the X Offset works fine...2) All AI-aircraft of my airport scenery have a jet exhaust effect. It happens often (randomly so it seems) that after landing these exhaust effects are hovering above the aircraft instead of behind the engines3) I want to make the de-ice effect only active from november to march. Is it possible to just use MOY=11,3; or do I have to split the effect parameters in MOY=11,12; MOY=1,3;Whatever I try (with SceneGenX), it doesn't work from november to march...Maybe someone can help me with these problems, thanx heaps in advance!Greetz, Arjan