Okay, I've been hammering away at this for hours so I am posting something about it.
This afternoon something hosed my wireless router, big time. Not sure what happened but it wasn't acting right. I managed to get it reset back to defaults and it worked fine. This is good because I thought it was burned up or something.
I managed to get all my settings and DHCP reservations back but I couldn't get my Airport Express to join the WPA2 Personal network. Eventually I loaded the old firmware image and took some screen shots before it failed again.
Apparently the Airport Express will NOT use TKIP WPA Algorithms. It must use AES. As soon as I set it to AES the Airport Express turned green and I had my music. I haven't tried TKIP+AES. Perhaps that will work too. I'm too tired to test it.
I searched high and low but all I could find was information on using WDS in this environment. I found nothing relating to what WPA Algorithms the Airport Express should use. So, here it is.