Thank you! it really works. Review -> (All segments -> All content) -> find a locked segment which was merged and hidden -> unlock the merged and hidden segment -> reedit source except tag since tag cannot be moved again in source segment -> However, apply the tag into right segment and then try to save target. To see hidden segment, go Option -> Editor -> Automation -> uncheck "Hide empty segments that have been merged"

ex) if segments 135 and 136 was merged, but they are different paragraph, 136 has a illustration tag, then target file would not be saved due to "illustration tag was moved" error. Solution: view all content in Review -> All content menu, and unlock the 136 segment. And then apply the illustration tag into the 136 segment in target, but not into the 135 segment. And then target file would be saved.

The key point is that if target structure is the same as original, the target file is saved.

It works again!

Fantastic! Tremendous help! Thank you.