In my experience, anything larger than maybe 1 or 2 TB worth of music really needs a dedicated server of some sort. Many of the "streamer" or "network player" devices (which is how Cambridge describes the CXN100) can accept USB drives with a moderate amount of music on them, but really aren't powerful enough to handle a larger library.
Something like a Lumin, or maybe Aurender, Auralic, or Innuos Zen would do a vastly better job of dealing with such a big library.
The other option is to check out Roon. You would run that on a different computer (either a dedicated server or just an existing computer on your network that you leave powered on all the time) and it handles all library management, album art, etc, then streams to your CXN100 over the network. Much much smoother more enjoyable process in my experience, although it has an extra cost and have a bit of learning curve to it. Once it is running I find it so much better than any other dedicated sever though, even the good ones like Innuos.