@grid Can you try and extract the PDX file from the zip archive and try sideloading that instead? I believe the playdate device software extracting the zip files provided by Itch. If not, ping me on Twitter (@notpeter) and I can DM you a working zip.
Yes! First I extracted the .zip to .pdx, but that wouldn't upload (I've had this problem for all .pdx files, they basically just get "stuck" uploading to the play.date site). But then I tried re-archiving it on my mac, and that actually uploaded just fine, and I was able to download/install it! Plays great, thanks for making it!