Ok...
I have managed to isolate the lower and upper ranges of MonthCal_GetSelRange(), thus:
Code:
SYSTEMTIME rng[2];

                    MonthCal_GetSelRange(hWndMonthCal, rng);
                    SYSTEMTIME low = rng[0];
                    SYSTEMTIME high = rng[1];

                    char buf1[30];
                    GetDateFormat(NULL, DATE_LONGDATE, &low, NULL, buf1, 30);
                    char buf2[30];
                    GetDateFormat(NULL, DATE_LONGDATE, &high, NULL, buf2, 30);

                    MessageBox(hwndDlg, buf, "Current Date", 0);
How do I get buf1 and buf2 into the MessageBox as a single unit with a pretty "to" in between?