Download your user import.
Then, when you open the .zip file in DiscorseHub, the app will give garbled text:
I tried to repro, but I can’t “open” the zip file in Discourse Hub. It’s a link so it will be downloaded with my default browser.
Anyway, should it be opened as a text file, the “garbled text” would be normal as it’s not a text file but a compressed archive file.
Can you describe precisely the steps you follow?
If these steps fail; than the forum might be a little outdated, like a month or two behind, but here is the site being tested: