I get a GPF with the following:
#define HH_DISPLAY_INDEX 2
HTMLHelp( oWnd:hWnd, "RMCHART.CHM", HH_DISPLAY_INDEX, 0 )
OR...
HTMLHelp( 0, "RMCHART.CHM", HH_DISPLAY_INDEX, 0 )
I also get a GPF if I include the full path to RMCHART.CHM.
Before getting the GPF, the standard window for displaying a CHM help file is displayed, and then the hated Windows error box is displayed asking if I want to auto-email the GPF error report to MS.