So, if I understand you correctly, you need to have two sections on each page - one with a set of data and another with the same set of data with some additional fields. Correct?
I'm not sure whether this will work, but it's worth a try. This assumes that you're using some sort of ID to link from your main report to the subreport and that the data is ordered by that ID. You'll have to tweak this appropriately if that is not the case.
1. In the main report create two Running Total fields. One that gets the minimum of the ID and one that gets the maximum. Reset on change of PageNumber.
2. Link from the main report to the subreport on both of these running total fields.
3. In the Select Expert in the subreport, set the formula so that the ID is between the min and the max ID's from the main report.
-Dell