Further clarification...Colorbox or Shadobox (are they now the same?) works as expected for browsing images in the "Image Galleries" feature, but not for browsing images inteh "File Galleries" feature. Even when the File Galleries are configured for storing pictures (see Editing and Plugins admin interface - General settings). This problem does not seem to be related to IE versus Mozilla or even the version of IE used - 8 vs. 7).
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