They are pretty close together, best if they are about 18" apart(too far for pecking reach),
and I think you really only need one(it's 8' long?) for 7 birds.
I don't think so.
There's is plenty of roost length for 7 birds.
Give her time.
Best to break this habit, go in after dark and put her on the roost.
Or close off the nests around roosting time.