I was not able to duplicate the scenario that you indicated, using the current release of Adagio Job Cost (April 2005). Taking a job that has the billings amount equal to the payment amount (thus a net balance due of zero), previewing the Job Status Report printed the billing and payment detail. I assume that you are printing with a detail level by Transaction.

Three things to look for.
1) What version/release of Adagio JobCost is installed?

2) If you print at a level of Phase or Category rather than by Transaction, you may not see the billing and payment detail, depending on the revenue level of the job.

2) Is the job closed? If so then you need to make sure that the 'Print report for' option includes selecting Closed Jobs in addition to Active Jobs.