I am a player in the author's campaign, and the writer of the last two pages of this edition, so this isn't an unbiased review.
Crimson Cutlass is the first (published?) game designed by Rahm and Hillmer, and it remains the best. There are multiple editions available of the game. The 1979 version, you don't have that. The 1989 version goes for way too much money on Ebay. The 2015 edition was released on Amazon Kindle and consists of four volumes. This version collects the four Amazon volumes and adds in another couple hundred pages of new and updated tables from the current campaign, all at a lower price. Therefore, this is the definitive edition of the game.
Pirates! Who doesn't want to play a pirate game! Character generation is super simple. Choose one of the four starting backgrounds, roll a dice to determine your character's Traits (No number ratings here, you're BOLD, or you're not), roll another dice to dertermine your starting skills, check off a couple of boxes, and your character is ready for play in under five minutes.
Cutlass contains rules for dueling combat, small-scale (squads) land combat, large scale (armies) land combat, seige combat, ship-to-ship duels, battles between Armadas, and much, much more. Most of the rules the Player will need to know are in the first 200-250 pages of the book.
Player's actions are resolved with a simple 2d8 roll - 3d8 if your character has the desired Advantage for the task.
Cutlass's mechanics require a shift in thinking for new players. The majority of the in-game actions are generated by tarot card flips on various tables. Most important for new players, one doesn't choose one's target in action in combat - the player doesn't say "I charge the enemy Captain and try to cleave his head from his shoulders with my Cutlass," but, instead, chooses one of eight combat postures, then flips a card on the relevant table. The card result will tell you what happens in that round.... Maybe you'll actually get to cleave the enemy Captain's head. Maybe you'll find yourself dodging a body falling from the rigging. Cards instead of dice yields more potential events on a table (154 vs 100), and more complex interactions, since, unlike a dice table where the same event could be rolled over and over, once that (example) 10 of Swords is flipped, it's gone... At least until the deck reshuffles.
If one can relax into the mindset of following and interpreting the deck, Cutlass is one of the most fun and rewarding games one can play.
For the Referee, Cutlass offers the most interesting mission generation and travel encounter system I've encountered, THE best experience system ever devised for any RPG, and a masterclass in world and campaign generation. Rules and guidelines allow the referee to create a campaign world from scratch with simple systems to track political alliances, generate rule of law, even reform the Church!
1500 pages of rules, ideas, encounters and tables to cover a staggering amount of situations. I can honestly say I've played Cutlass for almost 30 years and haven't come close to seeing everything the game has to offer. Cutlass's rules are streamlined and elegant, but the Mission Generation, Mission Encounter and Experience/Advancment system are what truly set Cutlass apart - and are also the sections easiest to adapt to "your favorite RPG." The Mission, Encounter and Experience systems can (and have been) adapt(ed) to any genre desired (for Fantasy Games, look at the relevant books for Conrad's Fantasy and Outlands, for Sci-Fi, look at the relevant books for Battle Born/Era 10!)
For about $0.01 a page, and the sheer wealth of useable material, Cutlass is hard to beat.