In the "Export Audio" pop-up, I've got everything set the way Scott indicates in his book (pp 435-436).  However, there is a ddrop-down menu called, "Preset" which is not address in the book.  I am wondering if my problem stems from this?  What does this "Preset" do?

Well, I thought I would reboot the computer.  After all, I did a download of the encoder activator thingy.  
 
I opened the project and began going through the export MP3 process.  Did the first pop-up window as I did previously.  Then, I clicked on "Export" and expected to get the 2nd pop-up window for "MP3 Export Options" but did not get it.  However, the MP3 actually exported to the file and it was 40MB.  I played it and it played the song in full.  I don't know what I didn't get that MP3 Export Options pop-up but I got what I needed to email this file.