When a panel is opened, 12d Model may set some default values for that panel.
However for most panels the user can supply the values to be used for all the panel fields each time a panel is opened. This information is stored in a defaults file for a panel.
The defaults file has the file ending .ddx (or a pre- 12d Model 12 format, .ddf).
If no defaults file exists for a panel, then the 12d Model defaults are used for the panel.
Please see the video below which shows how these Default files are created. Alternatively, we also recommend you look at customizing 12d Model Panels using Screen Layout Files, Toolbars and Usermenu’s.