You can add columns such as shown below:....
Report.BeginEditDate, Report.LastPrelimDate,
Report.LastSignDate, Report.IsAddendum,
DATEDIFF(minute, Report.LastPrelimDate, Report.LastSignDate),
DATEDIFF(minute, Report.LastPrelimDate, Report.BeginEditDate)
FROM "dbo"."Order", ExplorerSnapshot, Report
...