Hi,
The easiest method in ReportNet's Report Studio is just to add the items to your query (from the query explorer). Either that or add them to your report on the report page, then select and cut them (don't delete!).
In Cognos 8, you need to perform an extra step as some new technology was added to improve the efficiency of queries. For C8, in addition to the above you need to select your display object on the page (list, crosstab, chart etc) then go to the 'Properties' property and check the items from the query you wish to associate, or they will get ignored.
The box type property is definitely not required in this scenario.
Hope that helps!
MF.