Name.com support created a test account for me, here are the results:
1 - The issue which was preventing incoming mail sync is fixed in their "new, not the current production server" at the IP address given above.
2 - The workaround in latest AquaMail from last night works fine with their "current production server" fine too.
That's as far as syncing incoming mail goes. Marking read / unread works, star / unstar works too.
In other areas, things are not so good.
Moving messages between folders (including to Deleted) "sort of" works, again, server issue.
Searching for messages by text is broken, server issue again, and I believe K9 Mail and Gmail would be affected too.
Uploading sent messages works, but then then get deleted from AquaMail and re-downloaded again on next mail sync (the server won't let the app locate the just uploaded message). Server issue too.
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Properly implementing an IMAP server is a large, difficult task

The remaining server implementation issues above will be passed on to Mail2World (the server's software developer) by name.com support.