I found some code on the net to merge to pictures to a third picturebox using the following API calls:
Private Declare Function SetPixel Lib "gdi32" (ByVal hDC As Long, ByVal X As Long, ByVal Y As Long, ByVal crColor As Long) As Long

and

Private Declare Function GetPixel Lib "gdi32" (ByVal hDC As Long, ByVal X As Long, ByVal Y As Long) As Long

This all works fine but when I try to save the image using the SavePicture command the only result I get is a runtime error 380.

I can save all the other pictures on my form to a file (BMP) except the pic created with the API-calls.

What am I doin' wrong ??