Hello,

excerpt from MSDN:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/prntspol_7k1f.asp

LONG DocumentProperties(
HWND hWnd, // handle to parent window
HANDLE hPrinter, // handle to printer object
LPTSTR pDeviceName, // device name
PDEVMODE pDevModeOutput, // modified device mode
PDEVMODE pDevModeInput, // original device mode
DWORD fMode // mode options
);

fMode Description:
......
DM_IN_PROMPT Input value. The function presents the printer driver's Print Setup property sheet and then changes the settings in the !!!! printer's !!!! DEVMODE data structure to those values specified by the user. This value is also defined as DM_PROMPT.
.......

to me this means that the settings aren't updated in the PDEVMODE parameters but instead directly written to the global printer configuration

so you will probably just want to call DocumentProperties once to let the user change the settings in the dialog and then directly call it again with fMode set to DM_OUT_BUFFER to read out the settings the user just made ..

Regards
Christian