Count Unique values in multiple worksheets based on certain criteria

Hi guys

I really need your help in figuring out how to complete the below custom function in Excel.
The idea is simple . What I need is a function that will count unique values on certain worksheets in a defined column which will be the same for all these worksheets (this part is already solved with the below code) , but I want on top of this to report back the unique values given acertain criterion (this part is not solved yet).
Can you pls have a look at the below code and let me know what I am missing.
Thanks in advance for your support

ublic Function MultiSheetUniqueCount(Rng1 As Range, Rng2 As Range, Rng4 As Range, Criterion As Variant)
'Set up a reference to Microsoft Scripting Runtime in Tools > References
Dim Dict As Object
Dim Rng3 As Range
Dim Cell1 As Range
Dim Cell2 As Range
Application.Volatile
Set Dict = CreateObject("Scripting.Dictionary")
For Each Cell1 In Rng1
With Worksheets(Cell1.Value)
Set Rng3 = Intersect(.UsedRange, .Range(Rng2.Address))
If Not Rng3 Is Nothing Then
For Each Cell2 In Rng3
If Cell2.Value <> "" Then
If Dict.Exists(Cell2.Value) Then
'Do nothing
Else
Dict.Add Cell2.Value, Cell2.Value
End If
End If
Next Cell2
End If
End With
Next Cell1
MultiSheetUniqueCount = Dict.Count
End Function

Hi Mumps1

I do appreciate your fast response on this , I am attaching the relevant excel file for you to check.
As you can see the VBA formula in cell D2 and D3 in worksheet under the name "Master Table" it reads worksheets Lights_Utilisation & door Utilisation in column B:B and it returns the count of unique instances . Now what I want is for these unique instances to be also restricted on the values of column c:c of the "Master Table" , so when the formula works correctly the right numbers should be for Cyprus = 365 and for Greece = 5063 , now in both countries the formula returns the value of 5429.

Let me know if I have now explained in a more thorough manner
Thanks again for your generous offering to help me
Regards
Kyuss 21

The formula should lookup value C2 in the Master Table and return the number of 365 in cell D2 and lookup the value C3 in the Master Table and return the number of 5063 in cell D3 in the Master Table.