Hello.
Yes, I would recommend installing the latest AudioBox 1818 VSL driver (v1.3) found here -
http://www.presonus.com/products/AudioBox-1818VSL/downloads .
If you have trouble with the D8 i/o setup in Studio One you'll want to go to the "Song" drop down menu, click "Song Setup", then click on the "Audio i/o Setup" tab.
From there you can add additional tracks that route to the D8's inputs.
However, you will not be able to send output channels from your DAW to the D8s outputs. The D8 outs are direct i/o (meaning input 1 on the D8 routes to output 1 and so on, respectively).