Ok, Update on the MB dialog not closing, Steve remoted in to see what I was seeing. He dropped a pearl, that the Serial MB was set to polling at 25ms, but the actual time to complete the poll was 460ms or so. He noted that the ques on the windows event where stacking up since the poll was not completed. So he set my Poll to 600ms, and since that was greater than the serial completion time, it now CLOSES like it should. I.e. via the Red X or Exit.
Further I had my Serial Speed set to 19, and I bumped it up to 38 so it now completes faster, and I set the poll to 500ms to give me some wiggle room.
It now closes as it should every time.......
Thanks Steve!!