Kald af Funktion I workbook1 fra workbook2

Hvordan kalder man en vba funktion placeret i workbook1 module1, fra workbook2 ?
Der skal overføres et array af user defined type, i funktions kaldet.

vi anvender følgende metoder:

'--------------Workbook1.module1-------------
Public Type myType
    IDName As String * 50
    Data(1) As Double
End Type

Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pDst As Any, pSrc As Any, ByVal ByteLen As Long)

Public Sub TypeData2Array(arrArray() As Byte, typeData As myType)
  ReDim arrArray(0 To Len(typeData)) As Byte
  CopyMemory arrArray(0), typeData, Len(typeData)
End Sub

Private Sub CommandButton1_Click()
 
  Dim test As myType
  test.IDName = "Casper"
  test.Data(0) = 4.1
  test.Data(1) = 4.2
  Dim a() As Byte

  Call TypeData2Array(a, test)

  Application.Run "Book1.xls!Receive", a
   
End sub

'--------------workbook2 module 1-----------
Public Type myType
    IDName As String * 50
    Data(1) As Double
End Type

Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pDst As Any, pSrc As Any, ByVal ByteLen As Long)

Public Sub Array2TypeData(typeData As myType, ByRef arrArray() As Byte)
  CopyMemory typeData, arrArray(0), UBound(arrArray)
End Sub

public sub Receive(rec() as byte)
  Dim q As myType
  Call Array2TypeData(q, rec)
end sub
-----------------------------------------------
resultatet er :
  q.IDName = "Casper"
  q.Data(0) = 4.1
  q.Data(1) = 1.112536e-309 ????

Hvorfor er q.Data(1) ikke 4.1 ?
Hvis Data() dimensioneres 1 element større end nødvendigt(dvs Data(2) i dette tilfælde) da er q.Data(1) = 4.1

Hvad går der galt.. Kan man overhovedet anvende copymemory ?