I just spent an hour with the www.plyboats.com software (a demo) and enjoyed it. I used the Jim Michalak user guide from his list-of-past-issues. (www.apci.net/~michalak/1jan00.htm) In very little time I worked out the lines for a 10ft punt, only to discover that it wouldn't show me the offsets unless I forked over the cash and bought the program. Great anguish.
It's USD $145. Has anyone used it? Would you recommend it?