The 32-bit version (digilent.waveforms_v3.18.1_32bit.exe) successfully detected the AD2.
It is some sort of device detection timing issue. I noticed that I had the AD2 plugged into a USB port during the 32-bit install. The final step in completing the install asks if you want to run the application. This time I let the installer run the application. The AD2 was detected immediately.
Hmm...
Should the AD2 be plugged in before starting WaveForms?
I shutdown the 32-bit version. Unplugged the AD2. Started WaveForms. AD2 not detected. Plugged in the AD2. Still not detected. Hit 'Retry' on the pop-up 6 to 10 times. AD2 finally detected. Shutdown WaveForms. AD2 still plugged in. Started WaveForms. AD2 detected immediately.
I uninstalled the 32-bit version then installed the 64-bit version.
The startup behavior of the 64-bit version was the same as the 32-bit version.
So...
For me and my computing environment, it appears that before I start WaveForms, I should have the AD2 plugged into a USB port. If I miss that step, I should just hit the 'Retry' button on the 'No device detected' pop-up repeatedly until the AD2 is detected.