Custom FileDialog

I am using the API FileOpen dialog. I'm looking for info, tips, sites, direction, on how to extend the dialog with templates. I want to add a file 'Preview' feature. All the API dialog examples I've found, so far, do not cover this functionality. CCRP is not an option.

Thanks,
Rob

Why not create your own dialog? The standard windows dialogs are just that -- standard; designed to provide a consistant user interface.