In every project, the user has a series of format and style options to customize the appearance of his output. In the GUI, these options can be accessed and manipulated through Target Settings and Style Designer on the ePublisher Designer toolbar. For the ePublisher Designer engine, these customization options reside in the Format Trait Info (*.fti) files. Manipulating these files allows for customizing the location of options, creating or deleting options and parameters, or adjusting their values, or choosing a new default value.

Format Trait Info files must have the same base file name (that is, the file name without the file extension) as an XSL file in the current format in order to be processed by ePublisher Designer. The information displayed in the ePublisher GUI represents all Format Trait Info files associated with a given format. So, two or more Format Trait Info files may define a <Setting /> but would only be displayed once in the GUI.

When ePublisher Designer is generating output, the settings specified in Target Settings and Style Designer are consulted, stored in the project file (.wep) and incorporated in the final generation of output.