Hi,
I had the same problem, and will try the Firefox clear fix.
Problem remains, and this is what happened to me: Appears to be a calculated shipping issue (inserting extra international shipping sections, then mixing them up, not recognizing deletions) AND a local pickup issue (when all shipping options are cleared, and local pickup is selected, system still throws messages flagging non-existent package weight entries).
I was able to list something just now using a workaround. Selected fixed cost shipping, got it up on ebaY, then revised it to what I really wanted. Laborious, but it worked.
I (and no doubt many others) have a support request in on the issue.
Thanks!