OK, got one. Tried to add the "Big Linked" version of "A Bug's Life ..." entered all the attributes, clicked "Add" and came back to the same screen (with debug-logs generated). At this point, I've got something to work with and will report back when I've got a solution.
If you do a view source on the 4th step (with the Add button), do you get
name="id[1] value="Array"
instead of
name="id[1][value]" id="attrib-1"
Because that means you're seeing the issue.
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