you would nee to add each security assist page to the parent page as a dynamic plugin.
Lets say for example sake that the parent page is index.php
and that the Server variable to trigger the security assist pages is named "action"
go to the binding panel and click the pus button, select URL Variable and name it "action"
now on the index page add a dynamic plugin:
WebAssist -> Framweork -> Plug in -> Insert Dynamic Plugin
Click the lightning bolt next to trigger variable and select the action URL variable you created.
click the plus button for plug-in source to add a new plugin. Select the login page and set the variable value to be blank, this use the login page as a default.
Click the plus button again and select the profile page, set the variable value to "profile"
this will cause the profile page to load if the action variable is equal to prifile:
Click the plus button again and select the registration page, set the variable value to registration.
continue on adding each security assist page and setting the variable value that will be used to load them.
Now on the security assist pages, you will need to set the forms action to post to the index page and pass the correct action variable.
you will also need to go into each server behavior and set the redirects to use the index page and pass the correct action variable to load that page.