Understanding How ePublisher Works : Understanding Stationery, Projects, and Overrides : Project Format and Target Overrides
 
Project Format and Target Overrides
 
Creating Format Overrides
Creating Target Overrides
Managing Format/Target Overrides
Creating Super Overrides
ePublisher gives you complete control over the final output. However, some project modifications cannot be made through the ePublisher console. In these instances, you may need to override the default XSL files used by ePublisher to achieve the results you need.
When ePublisher generates output for the first time for a project, ePublisher reviews the format.wwfmt file in the folder for the appropriate format. This file tracks the actions required to generate the desired format. If there are no user customizations, all the files referenced by the format.wwfmt file are in the Format or Transforms folders in the installation folder hierarchy. By default, ePublisher first checks the project folder hierarchy for each required file before getting the files from the installation folder. With this process, you can override one or more default files by creating the same folder hierarchy in a project folder and storing a customized file with the same name at the correct location in the project folder hierarchy.
Note: You can override default files for all targets of a specific output format type in the project. You can also override default files for a specific target in a project without affecting other targets of the same output format type in that project. Overrides for a target override any customizations you specified in the override folders for a format.