It appears that when you use the mouse over condition to pick an object after you have filtered the same object in some other way, the moused over object is added to the previous SOL rather than placed alone in a new one.
In the included cap, when you mouse over any green or red circle, all red circles PLUS the moused over (regardless of color) one turn purple, rather than just the moused over red one (shouldn't happen for green ones).
Actually, I think the summary is a bit misleading. The same thing happens when all the conditions are placed in one event, as long as the "mouse over" condition is placed after the "overlaps" condition.