Something like this?
SELECT MAX(DayDiff(DownloadTime, GETUTCDATE())) AS DaysSince, NCA.NodeProperties.Nodes.Caption
FROM NCM.ConfigArchive NCA
GROUP BY NodeID, NCA.NodeProperties.Nodes.Caption
HAVING (MAX(DayDiff(DownloadTime, GETUTCDATE())) > 90)
ORDER BY DaysSince DESC, NCA.NodeProperties.Nodes.Caption
Just add it to a webpage by adding a Custom Query resource and putting this Query in there. Or load it up with SWQL and execute it there.