Could this be a sign of a learning disorder?

If it’s only the one game, I wouldn’t worry about it; maybe the game is poorly conceived or explained. I have had cricket explained to me multiple times (and football too, for that matter) and I have a hell of a time understanding either.

Don’t worry.

I have a hard time understanding other games too, especially games that have a lot of steps and levels

No. Either you are not entirely focused or you don’t really like the game so there is a kind of automatic “switch off”.

I’m this way about things that I could care less about, even if I try to halfway understand it.

I’ve played it numerous times and I really like the general concept of Ticket to Ride. And I’m quite focused when I play it. This is why I think it’s terribly frustrating

It might be one of those games that takes a while to develop a strategy for, and maybe that’s what’s missing that keeps you from visualizing the concept. Maybe the more you play, the more you’ll get a feel for how certain decisions can play out and help/hurt your overall play? And the more the game will develop a structure in your mind, rather than just being a series of rules to follow… But right now, as it’s new, you haven’t developed that strategy-knowledge yet?

So, for example, imagine you’re learning checkers for the first time (I don’t know Ticket to Ride, so I’m just going with checkers for a simple example). You’ve got a bunch of checker pieces, and at least in this case the rules are pretty simple… But even with checkers, the first time you play, you’ll have no idea what strategy to apply. Which checkers piece to move first? What will the other player do next? How do you get to the other end? How do you keep the other player from taking your pieces? Oh, and wait, what happens when my checker gets to the opposite end again? And can I take that checker of yours, or is it not in the right position? And should I? ... But the more you play, the better sense you’d have for how to answer those kinds of questions.

So (I’m guessing) you just don’t know the strategy yet. You will. In the meantime, I’d probably just take a best guess each turn and see how things work out (and if it didn’t work, then make a mental note and try something different in the next round.) Also try asking your friends questions like, “Why did you do x and not y?” and see if they have an explanation for you.

Maybe that will help?

Could be—if it typifies your inability to understand directions and instructions.

Not only do I never get the word puzzles on Wheel of Fortune… but after twenty years of watching, I don’t understand a single RULE of the game. But I am VERY good at Jeopardy. I have a learning disorder and am horrible at following directions. My lack of ability to follow or understand procedures is why I’m not good at math.