Watch out for this section:

If I were to select Out 1 here, my levels would be attenuated because of the position of the Monitor knob.
My personal preference is to select the Master Bus as the export source. This give me a hard reference within Sonar, and is not subject to monitoring.

For some reason, effects are no longer, um, effective, in the Master Bus, so all of my tracks and buses ultimately filter down to the Preview bus. The Preview Bus output is set to the Master Bus. I have a limiter and Voxengo SPAN in the Preview Bus as a final view of my project output.
This gives me the true output from Sonar, and I can trust it.
ymmv, hth.
ps: Good to see another EIE Pro user. It's an awesome interface, and deserves more exposure.