Have greated my own dialog class which uses it's own DLGTEMPLATE instead of a resource.
Problem: Ignores the size I send it.
Solution: Called SetWindowPos(...,....,...) from within OnInitDialog() which solves it but this is a sloppy
way of doing it as I'm asked the dimension's early in DLGTEMPLATE ->cx and cy
Bitmap (dimensions 600 x 300);
->cx = 600 // should be width in pixels of a bmp
->cy = 300 // should be height in pixels of a bmp
created window ends up nearly twice as big a the bmp.