The Gel Coat product looks neat, and may be right on target. Thanks for the idea. I'll look into their patterns. The color issue is not so important in as much as I plan to repaint the pattern part of the deck this year anyway.
I've gotten about that far as making a mold of the pattern when I decided to see if anyone else had words of wisdom. I have made a flexible mold about 6"square using stuff I got at Hobby Lobby ($9.99 or so). So far, so good. I used the top to the ice chest as the pattern. But now begins the experimentation and the inevitable failures/trial and error that I would like to bypass.
As for non skid, the paint I am using is Interthane Plus, and it has worked well on the flat surfaces using Interlux non-skid particles. The next step now is where there is the tread pattern, which, hopefully will be wherever there was a tread pattern originally. One of my concerns is whether those particles will settle in the grooves and essentially eliminate the deck pattern.