I was able to get auto-registration working with mechanize a few quarters ago (similar setup to OP); I got into two classes that way! I was just using SMS/emai

I was able to get auto-registration working with mechanize a few quarters ago (similar setup to OP); I got into two classes that way! I was just using SMS/emails from UW's provided notification system to trigger the script, though, so I don't think I was actually any faster than other students-just less stressed about watching for notifications.