Glad to hear you go it working, 18GB is a lot to upload for a game that is still yet to be complete.i did manage to make a playable version using a oversampling function on a newer version of renpy,
basically every 4k image to fit had to have it's filename end in @2 (i changed them all in a batch) and i had to change some hardcoded stuff too.
the final size is like 18gb so i never bothered to share tho.
Personally I would wait until all the (DLC) content is released before considering upscaling it as uploading that big of a file would take a better half of the day using my crappy internet.
But I would download a 4k version as I enjoy your sharper 1080p image version, it's just so much nicer to look at and play.
Thanks again for sharing your previous upscaling work with us, I really appreciate the effort you went through to make it