I think that you should be able to code in the code view instead of just view the MXML and Spark tags. If there already is a way to do that I haven't figured it out. So far Flash Catalyst looks like a "design version" of Flex Builder 3 or Flash Builder, only allowing visual components to be exported so Flex code can be integrated into the existing design. The basic parameters that can be set don't really offer a great deal of program control in the application.