Try to redownload and see if you can get it to work. Alternatively, join our discord for more feedback and troubleshooting options. Many more minds and eyes to help with the problem! This is something we have never encountered before.
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Just to tack on, as another dev: I just now downloaded the current version to check myself. Everything seems in working order, the images extract correctly as do all the music files, I opened them to confirm. Maybe your connection had a hiccup part of the way through and it didn't finish downloading all the way, I know I've had that issue before elsewhere.