Well, I took all of those suggestions before I read that post!
I plugged into a fairly small board last night, Auxiliary RCA outs > 1/4" in on MT, and the levels were quite low. I used the +25 boost on the MT and got decent enough levels and did some more boosting in Soundforge. The recording came out quite nicely.
On Wednesday, I used the Core Sound Cardiods > 1/8" to 1/4" adapter > MT, and got very light signals again. It was a fairly quiet acoustic/vocal ensemble concert. So I switched to the 1/8" plug directly on the fly and got enough signal to once again make a decent recording so that Soundforge could be used for post-production. That recording is currently being torrented here:
http://www.dimeadozen.org/torrents-details.php?id=69302At this point, the only distorted recording I experienced was pre-firmware update, while using different mics from the CSCs. I don't expect to have peak level problems, as long as I come prepared to use the 1/4" adapter, and use the proper line/mic setting.