Thanks for the bug report. I will try to reproduce it. This is a preview version, bugs are expected. Would you mind sending me a screenshot of that garbage sprite, to haplotenebra AT gmail? It will help me find the root cause. Thanks.
And thanks for playing. The game is free (like all my other retro games). People can make a donation if they want to. You're welcome to download and play it for free of course. There is no obligation to donate.