I kept trying things with the wx control panel (1 of the 2D panels) and finally figured out that wx radar did install with 1.2 and does work.  

Open the 2D panel, hit the PWR button and then the TEST button.  You should see a rainbow scan once across the HSI.  I don't know if this is the right order, but then I hit the WX button, which lit up, and then I had to hit PWR again until it stayed on.  I still didn't have any weather returns even though I could see CBs in the area, so during the climb I turned up the gain to 5 and the tilt knob to -3 and viola, I had the weather returns.  I tried WXA and got the same returns, so I don't know what the difference is between WX and WXA.  I guess I'll find out when the manuals are updated.

Hope this helps others.