Is this before or after you found the page to run it? It isn't meant to be downloadable until after the full C64-inspired fantasy console is released, at which time I'm going to make all the tools open source, but while they have the Patreon link commented out I'm keeping them browser-only. It will be downloadable within the week, though. I'm not sure why this page shows a zip file and a "play in browser" label when it doesn't let you do either from here... adding a link now.