Finding and Assigning hwnd for Microsoft Project

As part of a large macro I'm writing in Microsoft Project, I'm attempting to use the popular API code shownhere to open a file selection dialog that my user can use to select a file path. This code works almost perfect, except for this line:

If IsMissing(hwnd) Then hwnd = Application.hWndAccessApp

Obviously the original example is for an Access application, which I am trying to translate for Microsoft Project.  I've been looking all over for a similar piece of code in Project - how do I assign the appropriate hwnd in Project?

Thanks!

Dustin