As a way to teach myself more about Keyboard Maestro in general—and Custom HTML Prompts in particular—I wrote a little iTunes song info panel. When called, it shows album artwork (or a placeholder for missing artwork), and the song’s title, album, and artist. The final result looks like this:
The macro uses AppleScript and the Custom HTML Prompt feature, and it works reasonably well. If you’ve been curious about Custom HTML Prompts, this might help with your learning.
Here’s the full writeup; I welcome any improvements if you see ways this could work more efficiently.