Vantage Theme: Overlay images disappeared

Hello,
I created a child theme for Vantage and it worked just fine. I activated it for my site, came back the following morning, and the slider was not operating correctly. The overlay images had disappeared, and it no longer filled the page. It was working when I left it, and now it is not. The parent theme operates fine, so I tried putting the parent files back into the child theme, and now those don’t work either. I only changed demo.php (the slider), and parts.footer.php (the footer that shows text). When replacing those with parent theme, the problem persists. Any suggestions on where to look or what might be causing the problem?

Thanks!