A number of people emailed me reporting problems using the demonstration files for the ActionScript 3 SCORM class. Turns out the imsmanifest.xml file was causing the problems; apparently, one of the supporting XML files was corrupt. After creating a new imsmanifest.xml file and bringing in fresh copies of all the supporting XML files (the ADL/IMS stuff), the example launches as expected.
The new demo files pass the ADL SCORM 2004 Test Suite (both the SCO RTE conformance test and the Manifest Utility Test). They also work fine in Moodle (v1.8), which seems to be the LMS of choice for most of the people who contacted me.