Not the proto RTS but the boardgame digitization
The Dune Emulator is an almost to scale digital recreation of the original Avalon Hill board game. It takes place in the Herbert universe where Dune, the RTS game series takes place as well, but in terms of gameplay the difference is, as you would expect quite large. First of all, this is a game that some might call incomplete, due to the fact that it lacks AI; there is no NPC player to skirmish against. However, the game has a tutorial to allow you to familiarize yourself with the game, and, at the same time it has a system that will prevent you from playing without considering the rules. So no intentional or unintentional foul play will be possible. The game is thus part engine, part virtual digital board, as you'll need to hot seat against your friends. But if you get some of your real life boardgamers to try it out, it will sure prove to be quite fun. The game can also be played via mail and is a rather classic turn based kind of game. It has a RISK feel in portions, but it also makes use of card swapping mechanics. Difficulty wise, if you are a now and then player of serious board games, this will feel quite direct and immediate. So, give it a shot, for the novels, the TV adaptation or for the game series.