The item created by {{Anything > Page Deign > Controls > Text Box}} has an object inspector setting called {{Default value from calculation}} which shows a dropdown list of all RItems and lets the value be defaulted to the output of one.

For this feature we want the Calculation Grid Cells to show up in this list as RItems do. (Some technical details below about why this is not trivial)

That field in the object inspector expects a fully fledged RItem as input and will not work when passed something else, since CalcGridCells are referenceable in R and behave like a calculation it would make sense for them to work but they are not full fledged RItems as they are not an {{AnalysisItem}} directly.

There is quite a bit of behaviour built around that field that relies on being passed an RItem, including assigning and referencing them in QScripts. If it proves too difficult to make these referenceable perhaps we can add another field for CalcGridCells