Hi seasdes,
So I do understand correctly this is a progeCAD 2009 Professional problem, and is simply that you are never able to snap to any entity which is part of a group or just lines which are part of a group?
What happens when you create a brand new group in a blank drawing of, say, just four or five lines - does eSnap work normally with the grouped entities then?
Reason I ask is that I haven't seen your problem repeated in the lab. It could be because we are using the latest test version (which you don't have yet) so this might be something that is already fixed in the next free upgrade anyway. Just a though.