Skimming thru this thread I can answer some of the questions I saw.
The Cursader II is older than the Crusader M.
The Crusader II has 999 lines of program memory.
The RS232 port on a Crusader II is not quite standard.
Switch 2 & 3 (send & receive). They did this so you could use a straight cable (normally you would cross 2 & 3 in a standard RS232 cable.
Training for the Crusader II is available at the web site below.
Detailed training DVD's on the complete operation and inside tricks.
Tips For Manufacturing Training CD's, DVD's for Mastercam, SolidWorks, Inventor, G-Code Training & More
http://www.tipsforcadcam.com