Oh, I'm so both upset and relieved right now.TL;DRThe state of Xcode / Application Loader's underlying submission tool was corrupted. All I had to do* was delete the .itmstransporter folder in my home directory and try again. I no longer get cryptic validation errors when hitting Validate in Xcode, and I no longer get false missing images when submitting the app archive.*other than wasting valuable days of developement time searching for answers, trying every combo, and filing radars for the various failure cases *sigh*BackgroundThe real clue in all of this was the top of the log file, which showed something like this:An error occurred while starting bundles for the software update process. Transporter will try to continue. Unresolved constraint in bundle com.apple.transporter.asperasupport [7]: Unable to resolve 7.0: missing requirement [7.0] package; (&(package=com.apple.transporter.transport.service)(version>=1.9.6)(version<=1.9.6)) [caused by: Unable to resolv