To create a link to another website (like to a box.net shared file download) you have two options

In rich text mode: Type the name of the link, for example, “Download here” Then highlight the text and click on the insert/edit link button (the chainlink button). Insert the web address in the box that pops up.  Select “Open in new window”

In HTML mode: type

<a href=”http://the.address.here”> Name of the link (example–click/download here)</a>

Make sure to include quotation marks around the web address.  If you want it to open in a new window include  target=”_blank” somewhere in the first set of < >