Yes, I understand. I finally got the file downloaded through the app on my laptop, and from there transferred it over to my rendering PC. I have an ongoing conversation with itch's CS, and some rather unpleasent experience uninstalling the app from my laptop. I had to remove it manually in the end after uninstalling it through the app did no good.
Flowscape, I'm pretty impressed with. It works pretty well so far, and looks very promising. Good work.