Q1: How do I add links to the rotation?

Add links by editing the @links array in the script:

@links = (
    "http://example1.com|Example Site 1",
    "http://example2.com|Example Site 2",
    "http://example3.com|Example Site 3"
);

Format: URL|Description

Or use an external file:

$links_file = "/path/to/links.txt";

With links.txt containing one link per line in the same format.