I'll document the portals package when the rewrite is included in .LRN (tentatively planned for .LRN 2.1). The process of creating a portal has changed drastically (it is much simpler) so any documentation written for the .LRN 2.0 version would have to be rewritten, and I don't really have time to do it twice.
.LRN 2.1 is scheduled to be released mid-summer ...
