We need some specs on your system, if you don’t mind.
You say you installed it.
- Did you install the latest Tools for MR (not the disk, but the latest download)?
- Did you chose the Yamaha Steinberg ASIO FW driver when starting Cubase?
If yes to the above, you should have manageable latency, depending on your system specs. You can also set Direct Monitoring to ON, and record with ZERO latency.
Once the driver and tools software is installed properly, there are two places in Cubase to set up the MR816 hardware, one is in Devices/Audio Hardware Setup, and the other is in the hardware tab on the input channels in the Mix Console (as in the YouTube video you described). BUT, There is a bug with BOTH of these settings that may prevent you from accessing either or both of them at this time.
see:
for a workaround for the Devices/Audio Hardware Setup bug and a description of the problem behavior for the Hardware section of the Mix Console.
It’s confusing enough trying to use these features for the first time, then add on that THEY DON’T WORK THE WAY THE DOCUMENTATION DESCRIBES THEM, OR SOMETIMES AT ALL and you’re really SOL.
Good luck!