I created a directory in application/default/themes/ called HealthStatus, added a modified layout.phtml to it, created a public/css subdirectory and added my css file there (following the layout of the sample theme). Logged in as admin, went to the Global setup page selected HealthStatus from the User Pages Theme. Old theme still shows up. Select sample, and the sample theme shows fine. Any ideas on what might be wrong?
OK, on a lark, a changed the theme name to /hs/ (all lowercase) and copied the files there and it now works. The documentation should be modified or fix the issue appropriately.