I have created a plugin that will generate source code from the .form file that the Idea UI Designer creates. I've attached a README.txt, and an INSTALL.txt that describe how the plugin works and how to install it, as well as the GuiSource.jar plugin itself. I really like the Idea IDE and I really like the UI Designer that they are developing. The only problem I have is that because of the byte code manipulation the Idea IDE does at compile time, the Idea IDE is required to make any changes to the any UI screens.
I develop software for customers who would not be very happy if I delivered source code that they could not change using what ever tools they currently have, which is why I developed the plugin. I'm posting the plugin here because I know that there are several other Idea customers who are in the same situation as I am. I hope you find it useful.