I'll tackle the easy one first. The links island is easy. Here is what I have in the custom island for our Site Links:

Code
$body = <<<EOF
<a href="https://www.ubbcentral.com">Home</a><br />
<a href="https://www.ubbcentral.com/features.php">Features</a><br />
<a href="https://www.ubbcentral.com/docs.php">Documentation</a><br />
<a href="https://www.ubbcentral.com/purchase.php">Pricing & Order</a><br />
<a href="http://www.infopop.com/members/members.php">Members Area</a>
EOF;

For the login one you'd need to do a form that asks for the username/password and posts to start_page.php. It's similiar to the login.tmpl template just the form part however. If you can't get this figured out I'll cobble it together as soon as I get a chance.