Look and Feels
http://learn.adobe.com/wiki/display/Flex/Get+oriented+to+Flex - of course Adobe always does a good job, not liquid though.
http://www.appistry.com/community/wiki/display/cloudiq43/About+the+Platform - like some of the things they did here.
Changing Footer
http://confluence.atlassian.com/display/DOC/Editing+the+Footer - explains how to modify the property files inside of a jar file.
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