Hey, OP of the other thread that mentioned gallery-dl here. I tried installing gallery-dl via Python's pip command at first, but it didn't work for some reason I forget. I probably set up Python wrong. So I decided to install gallery-dl via Chocolatey instead, but unfortunately that was a few months ago and I don't really remember exactly how I set that up (or, for that matter, what Chocolatey even DOES as an application). After that, though, I just typed "choco install gallery-dl" in Command Prompt and it automatically downloaded everything gallery-dl needs to run, including Python.
Sorry if that's not too helpful a reply but unfortunately that's all I've got. Once you DO get gallery-dl running, though, I can help explain how to set up a config file and download from places that require logins and capchas and such.