Although it was never officially released, the UVB (Uidl Visual Builder) is a Tcl/Tk-based, useful tool to help in developing UIDL granule files for custom menus and dialog boxes. You can get the various files from here (they are no longer available on the ANSYS FTP site). This zip file contains files you can install and configure to get UVB up-and-running.
Also, the UVB Overview has been copied here. It is a presentation outlining the use of UIDL.
Please remember that UVB is unsupported and use-at-your-own-risk. However, with the UIDL Programmer's Guide mentioned above, these two tools help users greatly in developing their own interfaces for ANSYS.