Best Parameters/Settings for Full Screen Screenshots?

Hi, everybody. I sent this earlier, but it doesn't seem to have gone through. My apologies if this is a repeat question.

I am using SnagIt to capture screenshots of a software application. I then insert each screenshot, taking up the full slide, on a slide in Storyline to create a full screen system demo.

The screenshots look okay until I publish. Then they're blurry, even if I turn off image compression when publishing.

What are the best settings to use in Storyline to keep the images as sharp as possible? Any other best practices to share? I feel like I'm trying everything to preserve the screenshot quality, and Storyline is fighting me on it! It's pointless to have a system demo if learners can't read the text because it's so blurry. Thanks!