I have a list that has several different content types.  The list has a main workflow that uses a number of flexi tasks to assign reviews at different stages of the form.  Near the end of the workflow, there is a flexi task for manager approval that should show all of the fields available from the last content type (which contains all the fields of all the other content types).  However, when I customize the task form, I can only add fields from the first content type.  I've tried making the last content type the default, but the fields still aren't available.  What can I do to make these fields available on the flexi task form?