Loading Custom Data Type ?

The UDF loadCmdVariable might help you. I changed the properties of the data type, (END scares me as a variable name), but the idea is the same.

Type cmd
    begin As Long
    halt As Long
End Type

Function loadCmdVariable(ParamArray inputValues() As Variant) As cmd
  Select Case TypeName(inputValues(0))
      Case "Range"
          With inputValues(0)
              loadCmdVariable.begin = .Range("a1").Value
              loadCmdVariable.halt = IIf(.Rows.Count = 1, .Range("b1").Value, Range("a2").Value)
          End With
      Case "Byte", "Integer", "Long", "Double", "Single", "Variant", "Boolean"
          loadCmdVariable.begin = CLng(inputValues(0))
          loadCmdVariable.halt = CLng(inputValues(1))
      Case "String"
          loadCmdVariable.begin = Val(inputValues(0))
          loadCmdVariable.halt = Val(inputValues(1))
  End Select
  End Function

Sub Test()
  Dim xType(1 To 3) As cmd
  Dim i As Long

  xType(1) = loadCmdVariable(Range("a1:b1"))
  xType(2) = loadCmdVariable(Range("a1:a2"))
  xType(3) = loadCmdVariable(1, 2)
  For i = 1 To 3
      MsgBox xType(i).begin & ":" & xType(i).halt
  Next i
  End Sub