Excel 64-bit and comdlg32.dll custom colours - vba

Question

I'm trying to adapt the code in either here or here to open the custom colour palette in Excel 2010 64-bit but cannot get it to work. Code on both sites work fine in Excel 2003
One attempt
Option Explicit
Private Type CHOOSECOLOR
lStructSize As Long
hwndOwner As Long
hInstance As Long
rgbResult As Long
lpCustColors As String
flags As Long
lCustData As Long
lpfnHook As Long
lpTemplateName As String
End Type
Private Declare PtrSafe Function ChooseColorAPI Lib "comdlg32.dll" Alias _
"ChooseColorA" (pChoosecolor As CHOOSECOLOR) As Long
Dim CustomColors() As Byte
Private Sub Command1_Click()
Dim cc As CHOOSECOLOR
Dim Custcolor(16) As Long
Dim lReturn As Long
cc.lStructSize = Len(cc)
cc.hwndOwner = Application.Hwnd
cc.hInstance = 0
cc.lpCustColors = StrConv(CustomColors, vbUnicode)
cc.flags = 0
lReturn = ChooseColorAPI(cc)
If lReturn <> 0 Then
Application.Caption = "RGB Value User Chose: " & Str$(cc.rgbResult)
Application.BackColor = cc.rgbResult ' Visual Basic only ****
Application.Section(0).BackColor = cc.rgbResult ' Access only **********
CustomColors = StrConv(cc.lpCustColors, vbFromUnicode)
Else
MsgBox "User chose the Cancel Button"
End If
End Sub
Private Sub Form_Load()
ReDim CustomColors(0 To 16 * 4 - 1) As Byte
Dim i As Integer
For i = LBound(CustomColors) To UBound(CustomColors)
CustomColors(i) = 0
Next i
End Sub
This runs ok but doesn't show the dialog. I've also tried changing some LONG types to LONGPTR with no success. Does anyone know how to get this working on a 64-bit machine; or if it's even possible? Perhaps there's a new library?
Thanks
Edit: Slight rewording with offer of bounty...
How do I access and use this custom colour chooser (image below) in Excel 2010 64-bit (MUST work on 64-bit!) to set cells in Excel 2010 with the colour chosen and store the colour? The image is taken from Excel 2010 64-bit by selecting fill button>more colors>Custom
Valid XHTML http://img851.imageshack.us/img851/2057/unlednvn.png

Answer 1

Two things I would try. First, replace every use of Long with LongPtr.
Private Type CHOOSECOLOR
lStructSize As LongPtr
hwndOwner As LongPtr
hInstance As LongPtr
rgbResult As LongPtr
lpCustColors As String
flags As LongPtr
lCustData As LongPtr
lpfnHook As LongPtr
lpTemplateName As String
End Type
Private Declare PtrSafe Function ChooseColorAPI Lib "comdlg32.dll" Alias _
"ChooseColorA" (pChoosecolor As CHOOSECOLOR) As LongPtr
Second, replace the use of Len with LenB.
Private Sub Command1_Click()
Dim cc As CHOOSECOLOR
Dim Custcolor(16) As LongPtr
Dim lReturn As LongPtr
cc.lStructSize = LenB(cc)
cc.hwndOwner = Application.Hwnd
cc.hInstance = 0
cc.lpCustColors = StrConv(CustomColors, vbUnicode)
cc.flags = 0
lReturn = ChooseColorAPI(cc)
If lReturn <> 0 Then
Application.Caption = "RGB Value User Chose: " & Str$(cc.rgbResult)
Application.BackColor = cc.rgbResult ' Visual Basic only ****
Application.Section(0).BackColor = cc.rgbResult ' Access only **********
CustomColors = StrConv(cc.lpCustColors, vbFromUnicode)
Else
MsgBox "User chose the Cancel Button"
End If
End Sub
Private Sub Form_Load()
ReDim CustomColors(0 To 16 * 4 - 1) As Byte
Dim i As Integer
For i = LBound(CustomColors) To UBound(CustomColors)
CustomColors(i) = 0
Next i
End Sub
More Info
LongPtr Data Type
LenB Function

Answer 2

AFAIK 32-bit dll's cannot be used by a 64-bit application.
Use comdlg64.dll instead (if there is such a dll).
Using google reveals that there a host of viruses floating around on the net by that name.
So if comdlg64.dll is not on your machine don't download it from the net!
(Unless you want to experience zombieness).