I ended up switching to using getOpenFile and DirSelect on Windows. Still working on some of the quirks with the above two modules for UNIX (main complaint is they always open up in root "/"). If I can't get the UNIX issues solved, I'll use FileDialog for UNIX.
I found a problem with FileDialog in windows which forced me to switch to getOpenFile & DirSelect. FileDialog does NOT handle spaces in directory names. If you have a space anywhere in your path, the file listing window will be empty.