When trying to add a new slide to the Homepage slideshow, when selecting a choice from the "License settings for this image" pull-down, I didn't realize that "--Creative Commons--" wasn't one of the options. (If you're not familiar with CC, it's not obvious that all of the other options in the pull-down are types of CC licenses.) So, when I kept trying to select Creative Commons, it kept giving me a "License settings for this image field is required." error, which subsequently seems to have broken the titles on the homepage slideshow...
(Note: Could we take "--Creative Commons--" out of that pull-down to avoid confusion? Maybe rename the menu options "CC: Attribution", "CC: Attribution, Share-Alike", etc.? )