I am currently in a similar situation. I am using an old Soundcraft desk for the same purpose. Presonus does not make this easy, and sometimes impossible. I have a Studio 192 connected to a DP88 and a bayringer AD/DA. You first need to assign whatever channels/busses you have inside Studio One to the outputs you want, instead of the MAIN out. This is done easiest on the console, just under where it lists each channels input, it should say 'Main". click this and a drop down menu will open, select the output you want. Then you have to go to Universal control, select the output pair you are working on. Go to input channel 27, the DAW channels. The Main output goes to DAW 1-2. In Studio One, line output 1-2 go to DAW 3-4, and so on. Therefore, in addition to the main mix, you can only have three seperate stereo outs, or 6 mono. This also makes the entire nature of the 32 outputs on the 192 highly misleading... I can not get the ADAT outs 9-16 to work at all, and only 1-6 to work from the DP88. All of this by routing things very unintuitively. I blame Universal Control.