I figured it out -- It was evidently my virtual mat size.
To answer your questions: I used two different images - one from the SCAL library, and the other I created in Illustrator. When I tried ^A, I DID see the outline box going off the left side, but when I checked my original in Illustrator, there were NO extra nodes. I used the WSIWYG setting with the 0/0 point set to the bottom RH corner of the paper with the paper placed at the bottom RH corner of the mat. Both times it printed exactly where I expected it to. I was just getting started, so I'm sure there was nothing else on the mat. I tried the SCAL library image first. Got the Pause when it was finished. Tried my file next with the same results.
When you asked about the virtual mat, it made me wonder if that was the issue. Since I was seeing the dotted line go off the left side for BOTH images, I figured that was the likely culprit. I'm using the large mat that came with the 24". I had originally set the virtual size in SCAL to the match the dimensions on the grid. When I changed it to 8.5x11 to match my paper, the problem went away. Wish everything in life was that easy to solve!