Dave if you are trying to send waypoints from your chartplotter to SeaClear then maybe this is what you need....g7towin software. Google it and also look in the SeaClear Manual under the "Technical Information" and then "Using G7toWin to communicate with GPS".
Sorry, but that is as far as I can go. I haven't tried that. We do use SeaClear on the boat and it took us over 400 miles around the south end of Florida with no problems. We love the program and run it on a dedicated small 12 volt computer I made....
http://purplesagetradingpost.com/sumner/macgregor-navigation/Compter-Nav-index.html
...that uses less than 3 amps and we run it all the time while underway and plot all of our routes on it before starting on them. It is always connected to a handheld Garmin Map 76S in the cockpit and we can easily send the waypoints from the computer/chartplotter running SeaClear to the Garmin and we use the Garmin in the cockpit to go waypoint to waypoint.
If we are in a tight or complicated channel then I move forward in the cockpit where I can see the ....
...monitor in the cabin and give Ruth directions on where to go.
It is very accurate and easy to use under these conditions.
I've never tried to send waypoints to it though, but it looks like that is covered in the manual if you can wade through it. On our computer if you go to C:, then 'Programs', then 'Seaclear', then there are folders and one is 'routes' and another 'waypts'. I can see our routes in the 'route' one, but don't know the formate of the files themselves. Sorry I don't have more.
When we bought the Endeavour I moved the computer over to it and we will use the same system as we did on the Mac, explained above, for navigation there,
Sum
Our Endeavour 37
Our Trips to Utah, Idaho, Canada, Florida
Our MacGregor S Pages
Mac-Venture Links