Thank you Ian for your suggestion to check the CFIDE mapping.
I checked and on our 6.1 ColdFusion server, CFIDE is a virtual
directory on all domains. But on this new ColdFusion 8
installation, CFIDE was only a virtual directory for the Default
Web Site. Once I created a virtual CFIDE directory for the domain I
was testing from then the Flash Forms code worked. I wonder why the
new installation required this to be done manually.
The full solution appears also to require the modifications
outlined in the TechNote referred to earlier:
http://kb.adobe.com/selfservice/viewContent.do?externalId=ebd0cbe3&sliceId=1
UPDATE: The changes suggested above include changing a
setting so that the generated Flash is kept. However that allows
these generated files with random file names to keep building up in
the web directory. So I changed it back to the default of FALSE and
the Flash Form code still is working. Thus, as far as I can see,
one can skip changing the flex-config.xml from false to true in the
code:
<keep-generated-swfs>false</keep-generated-swfs>