2013 sp1 64 bit
Boss extrude2 fails to show when flat patterned, select show and you can see it, un-flatten, re-flatten and it fails to show again.
I'm not sure what's causing the problem you describe, but there is a mis-match between the faces of Edge-Flange7 & 8.
The mis-match does not exist when in the flattened state, so Boss-Extrude2 shows OK when unsupressed & merged in the flat, but it becomes supressed in the formed state because of the mis-match.
Yes you are correct, it works now and so was me!
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