The retro style look interesting but i can't download the demo, I think you have a issue of how you configure the link, it don't has problem with the wallpaper zip.
So an easy fix is put the exe file inside of a winrar file and configure it as an autoextraible. Consider that links are tricky somethimes work in localhost but not in production with a real url
PD: remove the ".html." of the link redirect to an empty page.