Public Function fnReplace( _
  ByVal strText As String, _
  ParamArray varItems() As Variant) As String
    Dim lngI As Long
    Dim lngPos As Long
    Dim strReplace As String
    
    On Error GoTo HandleErr
    
    Do
        lngPos = InStr( 1 , strText, "%")
        
        If lngPos >  0  Then
            strText = Left$(strText, lngPos -  1 ) & _
              varItems(lngI) & Mid$(strText, lngPos +  2 )
              lngI = lngI +  1 
        End If
    Loop While lngPos >  0 
        
ExitHere:
    fnReplace = strText
    Exit Function

HandleErr:
    Select Case Err.Number
        Case Else
            MsgBox "Error: " & Err.Description & " " & _
              Err.Number
    End Select
    Resume ExitHere
End Function

Public Sub TestReplace()
    Debug.Print fnReplace("Текст с меткой %c и меткой %d", _
      "Метка C", "Метка D")
End Sub