I set a brand color but the buttons still look blue
Save the Branding tab, then reload the page you’re looking at. If it still looks the same, your site or browser may be serving a cached stylesheet. Clear the cache.
My button labels went dark instead of white
Working as intended. When white text wouldn’t be readable on your brand color, the plugin uses dark text so the label stays legible. See About the brand color readability check.
The readability check says my brand color fails
Only one check can fail: your color as a button shape against the white page, which happens when the color is very pale. Save works anyway, since it’s a warning. A slightly deeper shade usually clears it.
My logo only shows inside a course
That’s where it goes. Every other page already shows your site’s own header and logo, so the plugin doesn’t add a second one.
The course page runs edge to edge and the image fills the screen
Go to Settings, then Catalog, then Course page. Keep the page to a readable width and cap the image height. See Course page layout.
The Register button looks like plain text
The plugin styles its own buttons whatever your theme does to buttons. If it still looks plain, check for custom CSS in your theme or page builder that targets buttons inside the form.