I was trying to load an flex-built swf into a swish-based movie and FAILing, doing some research led to:
(AS1/AS2 and AS3) run in different "virtual machines" within the Flash Player. Like many product upgrades, AS3 based SWF's can load AS1/2 based SWF's but AS1/2 can not load an AS3 based SWF.
ActionScript 3 is a totally new product and not a simple upgrade of AS2. Adobe made a "business" decision to not include "legacy compatibility."
which comes from here: http://forums.swishzone.com/index.php?s=b8a808adb9b5dea0e88c5c6cedb97018&showtopic=60051&st=0&p=259340&#entry259340
One strategy I was told could be used is to create a swf that loads the AS 1/2 swf and then on some event loads my AS 3 movie. Thing is, that event is in the AS 1/2 swf, so is this possible?