Benazir,
Pages related to the Reverse Proxy (which is providing "Point of contact" functions for the federation) are found in the WebSEAL management root. The main thing here is the login page (for identity provider) when you are using built-in authentication methods.
Pages related to federation flows (where-are-you-from, consent pages, scripted POST pages, SLO pages, federation pages) are all located in the Template Files under the federation menu.
In general, you shouldn't need to change mapping rule or other configuration in order to pick up changes you make to these files.
It would be easier to give a more specific answer this question if you provided some detail on what you want to achieve with customization.
Jon.
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Jon Harry
Consulting IT Security Specialist
IBM
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