Thanks for provided scene. I can confirm, that in some cases high values used for Transform - Translation can produce that kind of troubles. Actually, these transformations are applied after final distribution calculation (as these depends on other parameters). By setting high values, could happen, that items previously not included in "trimming list" can overlap the area border and they're not trimmed correctly. We'll try to fix that behaviour. Meanwhile we strongly advice to use lower values (like up to -50 to 50).