I'm running into the same issues that you are, Stax_911 (and I'm using the same roadmap to import). I found a reply on the forum from gkellum [Eventide] that mentioned the *.H9z format as a form of compressed zip file. It went on to suggest renaming *.H9z to *.zip, then extracting the preset or preset list. I'm sure that it referred to an ealier H9 Control version.
Since I compressed the file *twice* (zipping all of the H9z files together), maybe that corrupted something. Just moments ago, I downloaded my own upload, extracted it to a separate folder, and tried importing. The Preset List won't import – period, and some – but not all – presets import as singles. Let me try a few more things (including .syx file archiving from FactorLib), and see what I can come up with.
I'm tempted to delete the download until I sort things out, but perhaps Eventide can use it to analyze the export / import process from a user standpoint. Next time, though, the new upload won't "double-compress" the files. BTW: I exported everything from either the Preset or Preset Listing screen, not the Settings tab. I know of no other way to import (but drag-and-drop would certainly be welcome).
Thanks for your feedback, Stax_911. I'm going to get this download fixed. The irony is – I was waiting for PitchFactor support in H9 Control to compile all of these presets-on-paper. And when I tested the files before upload, I must have clicked on several of the presets that imported smoothly. Back to the virtual drawing board …