This specifies the name of the file where the default prefs are held.
The format of the file is:
; comment line
A Comment
GadgetTitle1=SettingsPrefix=DefaultValue
Used where "SettingsPrefix=DefaultValue" is to be written
GadgetTitle2==List Values=Default Values
Used for an MLIST where multiple switch values are to be written.
Prefixing a line with a + means that that setting will not be reset to the default value when "Reset To Defaults" is chosen.