OK. I can duplicate it now. So far it only happens with static pictures (places where there is a link back to the file in the template directory) -- there doesn't seem to be a problem with on the fly graphics. The path name to the link doesn't include the name of the course after all so when the course name is changed the alias address still goes to the old address. I'll make sure that the new addressing mechanism is sensitive to the name of the course as well as the user data. That should prevent this particular problem.
broken links after rename of course
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