ASIO4ALL in Cubase Elements 8 with UR12

I have been using ASIO4ALL in Cubase AI 7 and Cubase Elements 8 for a while with an M-AUDIO M-Track device.

I am now adding in a Steinberg UR12, but the UR12 does not seem to be seen by ASIO4ALL as a device and once I load the Yamaha/Steinberg USB drivers, then I change the ASIO Driver to Yamaha Steinberg USB ASIO, but that can only see the UR12 device and not the M-Track.

How can I get both M-Audio M-Track and the Steinberg UR12 working at the same time if they use different ASIO solutions?

I need M-Track for stereo input from a keyboard and I need UR12 for mono input from a Phantom power mic - all at the same time.

Windows 10 64bit. AI 7 and Elements 8 both loaded on a desktop and on a laptop with USB E-Licenser.