All, I got a couple of reports that some of the layers were being authenticated on the outside. I think I have them all exposed now, so they should all be viewable for those that were interested in comparing the AGG 24bit PNG and GD 8bit PNG outputs which both have transparent backgrounds enabled, side by side.
See here for the test site: http://gis.ci.stpaul.mn.us/gis/gismo_public/html/?mapbook=/datasets/CONFIGS/SAINT_PAUL/PUBLIC_WORKS/MAPBOOKS/TS/gismo3_test_public.xml# If someone could test this real quick and get back to the list, it would be appreciated. bobb