You just need to find a link to the game rules (on BGA, or on the editor's website), read it carefully, watch one or two games as a spectator with the rules on a separate window, then create an unrated game and explain it's your first game and you're learning. That's what I did for Takenoko and now I play this game without any problem.
Except Gomoku, Reversi and Puerto Rico, I couldn't play any of the other games, but if you look at my profile I have a record in over 20 games (over 15 with over 1600 ELO).
It only read the rules, take some practice games to get a good strategy, many are afraid of "losing" and prove that even a game.