Hi,
I tried this 3 years ago and gave up.
Tried it today and many problems still there !
If I copy an image and want to paste it into a group node, it does not paste it pastes the previous image I copied
To clear it i have to paste the image anywhere into yEd (but must not be pasted into the the group node) then cut then it and then it can be pasted correctly into the group node 
Also another bigger problem, I have a group node correctly set with a large image, with a single wire to the top of it.
If i open it and then on closing the group node, the wire connection has moved to the bottom of the node and a long straight wire is added ?
Hopefully these problems will be fixed, thanks 
