To edit a custom image with a Metal Appearance should be no different on your end. You edit the image and scale at the Relief Pattern, where as you would do this on the Bump mapping of a Generic Appearance.
See this video http://www.screencast.com/t/PVXhd5cn3
I just updated to SP1.1. I tried this when on RTM and it was no different.
Regards,
Kenny
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