To select a TEX format file, simply click on the corresponding radiobutton.
The environment variable specified by the CURRENTFORMAT parameter
is set immediately after this operation. So you don't have to quit the program
to set the TEX format file.
The 'SAVE' button copies the current setting to the environment archive
EnvArc:. You can quit the program either by pressing the 'DONE' button,
by selecting Quit from the menu, by closing TEXFormat's window, or by
pressing AMIGA-Q (or the key 'D' in the MUI version).