Untouched but confirmed NMT translations are not being imported into the WS memory

Scenario:

1) Download translation package from WorldServer and open in Trados Studio.
2) Set up project in Trados Studio, add DeepL NMT app.
3) Pre-translate file; all segments with less than 75% match are NMT'd.
4) Open file for translation/post-editing.
5) NOT Modifying but confirming an NMT match: The blue NMT box remains.
6) Modifying and confirming an NMT match: The blue NMT box is "cleared" but the NMT text remains (i.e. transparent box containing text NMT).
7) Translate file until end; return package to WorldServer.

The translation units from 5) are NOT imported into the WorldServer TM. The translation units from 6) ARE imported.

We are using the latest (updated) version of Trados Studio and version 11.3.5.4758 of WorldServer.

Is anyone else having this problem? Is there a known fix other than manually adding and deleting a space to each unit?

I am NOT adding tags to this post because everytime I do, it erases my work and reloads a blank browser window.