Preview displays blank doc in XML Publisher

Please forgive my newbie questions, as I'm new to Oracle E-biz and especially BI Publisher.  I have a task to modify a custom report based on the seeded Check Writer report in Payroll.  When I try to Preview the seeded report in any format (PDF, HTML, etc.) I get a blank page.  There are other seeded reports that display properly (like PTO Balance), but not the Check Writer (and not our custom report based on the Check Writer).  My computer was used by the previous developer who created our custom report, and the computer was not reimaged or reformatted, so