There is nothing inherently unique about the files generated by the UI Designer, except that they should remain fully or partially under the control of the UI Designer if you wish for it to update them properly after you perform edits within the UI Designer.
The goal of the UI Designer is to produce the exact same files which you would produce manually to create your application's user interface. These files are then processed by the Carbide.c++ build system exactly as if they had been created manually.
Topics in this section include: