That's strange >.< I wondered if it might've been a problem with itch's servers at the moment or something, so I tried downloading it myself, but it was fine. I was able to get the full download in about 2 minutes.
I'm not that knowledgeable about what could cause issues with downloads but I guess it could be a problem with your net provider. I know when I'm trying to download stuff on my PC via wifi, it cuts out a lot T_T even for small files! It's kind of a nightmare trying to download anything over 1GB, haha.
Anyways, I don't know if it will help, but I uploaded the Windows version of the game to Google Drive, so you can try downloading it from there and see if that's any better :3
https://drive.google.com/drive/folders/1UEM_Orgxv8No7tUq7VjhAoLTAW4m2mSi?usp=sha...
With any luck, that will help :3