Running NDPS v 4.0.7 on a NW6.5 SP7 box.

Using iPrint client v4.36.0, I can't open a print map file for editing.

I can run the MAPTOOL.HTM application, but when selecting File -> Edit,
I do not get a dialog box to open the print map file.

I've tried IE 7 and Firefox 3.0.1 with no luck. With Firefox, when
opening maptool.htm, it's reported a plug-in is missing, but the plug-in
is unknown.

Where to go from here?