Hi,
I read a lot about attribute panel issues and (unfortunately), since I am going to list something in ebay.com, I had to face with attribute too. The panel has a very annoying issue that seems to happen very often but apparently randomly.
When you click on “attribute” in right hand column, the pop up windows open. Sometimes, it opens differently: a separated window instead of the usual “linked” pop-up one. As soon as this separated window opens, it shakes and in bottom line I read “selected listing: (null)”. If I fill information and close the window, it does not save information (see “aluminum”, I had to close and reopen two times). When I opened it for the third time, it finally opened the usual “linked” pop-up window and information saved correctly.
Now I understand those users who had troubles with attributes 
Federico
