I used a Garmin 45 when I had my M23 and would download waypoints/routes from Navmaster III charting software under Win3.1. This software is now obsolete but check with Peter Jacob's GPS website for the latest software. I still use Navmaster III on my Nonsuch 26 but it warns me that is non-2000 compliant.
Dick

Steve & Diana Parsons wrote:

Does anyone on the list have experience with GPS mapping software. I bought a Lowrance GPS/Sonar unit, and am curious if anyone knows the tricks that would be most beneficial for creating maps/routes/waypoints/etc.. Answer offline if this is too off topic. Regards, Steve