SamT many thanks for responding.

Ok, I have added the following VBA to the users Personal.xlsb under : - VBAPRoject(PERSONAL.XLSB) > ThisWorkbook

Then saved and debug > compile , which all went fine.

Then I closed down all the excel applications > then re-opened excel with a new blank worksheet

and attempted to double clicked within the range G2:G1000 and nothing happens 

Sub ThisApp_SheetBeforeDoubleClick(ByVal Sht As Object, ByVal Target As Range, Cancel As Boolean)
     
    If Sht.Parent Is ThisWorkbook Then Exit Sub
     
     'If all Workbook will have the same Root
     'If not Sht.Parent.Path = ??? Then exit Sub
     'If all have a similar name part
     'If not InStr(Sht.Parent.Name, NamePart), then Exit Sub
     'Do Stuff
Dim MyRange As Range
Dim IntersectRange As Range
''''Dim EndRow As Long
'
'
'''''Application.ScreenUpdating = False
'
'''''EndRow = Range("D" & Rows.Count).End(xlUp).Row
'''''Set MyRange = Range("G2:J" & EndRow)   'last row
Set MyRange = Range("G2:G1000")   'last row
Set IntersectRange = Intersect(Target, MyRange)
On Error GoTo SkipIt
If IntersectRange Is Nothing Then
    Exit Sub
Else
'
'
'
Target = Format(Now, "ttttt")
MsgBox " still need to format cells with ...custom macro hh:mm"
'
'''''Application.ScreenUpdating = True
End If
ActiveCell.Offset(, 1).Select
'
'
SkipIt:
Exit Sub
'
     
End Sub