The Preference settings are divided into a number of subsections. These correspond to different modules of the Exmh implementation. Use the buttons in the main Preferences window to select various sections.
Information about each setting will appear if you click on the short description of the preference item.
There are three types of options you can set through the Preferences dialog:
The preference dialogs are tied more directly to exmh than you might expect. If you toggle a radio or check button, the underlying variable that controls exmh is changed immediately. The Save button commits your settings to disk.
The Save button will save your settings in an exmh-defaults file in your ~/.exmh directory. This is an Xresources-style file.
The Reset button will restore the settings from defaults and your last saved preferences file.
The Dismiss button leaves the settings as they are displayed and removes the pref window. Thus, those settings that "take effect immediately" are still in effect but they are not saved to your pref file.