On many hosts, Orphans will time out after 30 seconds for larger sites. I did find that it crashes when a static resource has an invalid path. That might happen with static elements also. It might also have trouble with weblinks and symlinks, but I don't think so.
It does run for me on a multi-context site, but if the site is large, the search for orphan chunks (which takes the longest) will time out.
I'm working on a standalone version that will run from the command line or as a cron job with no time limit. It should be out in a few days.
