[gd~...] -- This code is for inclusion of graphics data. Normally, this command is entered in a file as a result of using DBT's Layout: Picture menu item.
A picture can be inserted anywhere by using Layout: Picture, Add. All other items in the Layout: Picture menu can be used on when the cursor is positioned at (just before) a [gd~...] code. Getting this position right is most easily done in Coded View (Alt + F3)
It is not practical to enter this command manually, e.g. by the direct code list, because the graphic image information is included with the command as a parameter, and that information is specially coded and usually lengthy.
For the same reason, the command parameter is not shown in DBT's coded view.
The 12.2 CD comes with a program called "QicTac" which can be used to create picture files to be inserted into DBT documents.