Okay, I managed to resolve the problem on my own, with some time. The basic method is to just ignore the manual completely, as it's wrong.
The "Nodal MIDI" ports don't appear in Windows at all. If you want to use it with other software, you need to create virtual MIDI ports of your own. It hints at this but explains it completely incorrectly. MIDI Yoke, which the manual recommends, also doesn't seem to work on Windows 10 64bit at all, as far as I can tell.
I downloaded a free tool called loopMIDI from here, and that did the trick:
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