Copy / Paste macro giving errors

I have a copy/paste macro and my copying range has some blank cells in it and some cells that are 0. When I paste the data it fills in the blank cells with 0's.

Is there some code I can add so if the value is a zero it shows a zero and if the cell is blank it shows a blank?

This is my original code. Thanks

Private Function GetValue(path, file, sheet, ref) 
     '   Retrieves a value from a closed workbook
    Dim arg As String 
     '   Make sure the file exists
    If Right(path, 1) <> "\" Then path = path & "\" 
    If Dir(path & file) = "" Then 
        GetValue = "File Not Found" 
        Exit Function 
    End If 
     '   Create the argument
    arg = "'" & path & "[" & file & "]" & sheet & "'!" & _ 
    Range(ref).Range("A1").Address(, , xlR1C1) 
     '   Execute an XLM macro
    GetValue = ExecuteExcel4Macro(arg) 
End Function 
Sub TestGetValue2() 
    p = "C:\Excel Test" 
    f = "Terry 2.xlsx" 
    s = "Sheet1" 
    a = "D6:G9" 
    Range("A1:D6") = GetValue(p, f, s, a) 
End Sub