Thank you! By the way, I had the same issue with my MiSTer as hayesmaker64 (post above). Same with BMC64 that I used for the longplay. However, in my case, I hadn't set True Drive Emulation off and Virtual Devices on. Instead, I had Action Replay + True Drive Emulation enabled (that's my standard configuration for maximum compatibility).
It would be highly recommended to address this issue in Version 1.1, as it's quite likely to have the same issue on actual hardware. FYI, I used the version by Excess on csdb for this video, and it worked flawlessly. But, after you mentioned "not spoiling the very end", I assume there's some sort of ending after the congratulations screen(?). However, in this version, it wouldn't load after I pressed the fire button on it. Nonetheless, I thought that this screen might have been the end of the game, otherwise, I might have spoiled the "very end" in the video. 😉