Well, I would set it up for TV using the built in search function or manually with setup code 0178 (Press Setup until 2 blinks, Press TV, Enter 0178. The remote should blink twice).
Then, assuming you want to get the same functionality as the HDMI button on the OEM remote, either A) Copy the HDMI signal from the OEM remote to the OARUSB04G 1. Press Learn until 2 blinks (in upper right corner of the remote) 2. Press TV 3. Press e.g. TV Input (lower right corner) 4. Place OEM remote nose to nose with OARUSB04G about 1-2 inches apart. 5. Press the HDMI button on the OEM remote. 6. Press Learn until 2 blinks to exit learning mode, assuming you have no other functions to learn
B) 1. Press Setup until 2 blinks 2. Press TV 3. Enter 994 (should get 2 blinks) 4. Press Setup (don't hold it) 5. Enter the EFC 00174 6. Press e.g. TV Input You should get 2 blinks. If you don't, the remote may have come with old firmware. Go to Simpleset.com, and click on Restore Remote, follow the instructions, and then try the above procedure again.
If instead you'd like to be able to select any of HDMI1, HDMI2, HDMI3 with a single press of a dedicated button, follow the above 994 procedure using EFCs HDMI1 00193 HDMI2 00191 HDMI3 00195 You might for example assign these to the colored buttons. A major resource is post #84 in the Vizio discretes thread. If you want to do more extensive programming consider installing RMIR.