Crazy Machines 2 is a sequel to Crazy Machine, not counting Crazy Machines 1.5, released in 2008. It's a game of genre of Incredible Machines, where you build a machines out of many details that will accomplish the goals in one way or another. Or more exactly, you feel the needed spaces with limited amount of elements to find one of few correct solution. More of classic puzzle than anything sandboxy you see lately.
Game even supported PhysX new-by-then hardware.
And now, about how it runs nowadays on Steam.
It runs badly!
First, many people have trouble at making this game start at all. I didn't had problem with launching it. You should check demo version first somewhere to see if game will run for sure or not. If you will have trouble then try to find and (re)install OpenAL.
Then I personally had physics not work in this game. Managed to fix it by reinstalling PsyhX and then rebooting computer. Though I have feeling that rebooting was enough, after all game itself should install PsyhX drivers. Anyway. Try to reboot computer first after installing game.
Once you are past launch troubles (which you may not have), you still have the amazingly screwed physics in game itself, which is quite a really bad thing for physics-based puzzle.
The thing is that physics are not reliable. Tweaking some elements may change the resulting behavior of other elements that aren't connected to the one being tweaked in any way. You may be changing gears around in one part of map and it will somehow make baseball miss the bucked while rolling off slope somewhere else, for example. It's quite frustrating when you got solution right, yet it may not work until you play around with objects.
That, and the way that physics work in game seemed to slightly change from when it originally came out. What it means is that some solution don't work anymore. Now, it doesn't affect Crazy Machines 2 much, I enjoyed beating it fully. but there is a single puzzle in Bonus Labs, puzzle number 18, where official full (with bonus objectives) solution doesn't work. You can however get to see the full solution that community figured out in a list of high score records, by watching replay, once you rush through puzzle without completing bonus objectives.
DLCes seem to have more of broken puzzles, so watch out for those.
Puzzle instructions, which funny professor with overgrown moustaches narrates (instead of being annoying by popping in randomly for some always-repeated comment like in the original CM), also have small problems. The on-screen drawings that point out objectives appear much slower than voice reads the text. Even more, I noticed that some of the later puzzles have intros where voice narrations and text have little differences. And there was even a puzzle where text and voice instructions put "in what order it should be done" incorrectly, different from on-screen drawings!
As you can see, Crazy Machines 2 is full of technical flaws. Which is quite a shame, because it's superb sequel to Crazy Machines.
It has a much more "high-budget" feel to it than previous title, sporting modern-by-then shiny graphics, support of more complex physics (Like, ropes can be hanged without being connected to anything, useful for just pushing objects.), even 15 themes, with their own decoration and music. Soundtrack is a bit too much of "stereotypical local", but got nice pieces, like Caribbean theme that sounds slightly like something from Monkey Island . On bad side it's hard to understand whole puzzle system from the first look, new graphics/style are quite messy, also having useless decorations mixed in.
It also introduced new complex systems of gears and laser, making them often main focus of puzzle. There are also robots made of 3 parts and switches on which you can place switch of any given type, like button or timer clock. Instead of puzzles being one-trick physics stuff, you often will have to manipulate whole system of gears, lasers, electricity, switches. Which isn't such bad thing, especially knowing that physics are buggy here.
And every puzzle in this sequel concentrates on mostly figuring out where in the system to place each elements. There are almost no puzzles where the only thing you have to do is pixel-perfect placing of elements, unlike original Crazy Machines. I mean, not when you figure out how it should work, but when you are busy tweaking placement, being frustrated with it. I like Crazy Machines 2 approach so much more!
Not to mentioning that it saves some work when it comes to precise placement after all by having a minimal step which elements can be moved by, so to say.
Game also gives you mandatory and bonus objectives, while also providing with text clues and other hints, giving it less frustrating moments. Unlike Crazy Machines, where you either figure out solution to some-super-tricky puzzles or don't progress at all.
Overall, you will get 150 main puzzles to solve, with last 40 of which being hidden until you beat all previous ones properly. There is also 10 tutorial puzzles that you should do. 20 more Bonus puzzles. And 20 more bonus puzzles that were made exclusively for PhysX hardware. No, you can't access those. So no idea what to expect in them.
You also can design your own puzzles for your own amusement or to send it to others. Yes, you can download and upload your labs in the game to the server. And editor lets you do quite a lot of things too. Though, for some reason it has some elements locked. The requirements for those is to get some awards in main campaign, by, for example, using fireworks few times. Bad thing is that it doesn't tell you what exactly you are supposed to do to unlock them, from what I know. In all honesty, I didn't try making my own labs or try using others, so I can be wrong.
Overall, I can recommend this to only those who are ready to handle technical difficulties and those who loved Incredibly Machines games. It's good sequel and I can overlook all trouble I sometimes had for all fun I had with puzzles that didn't feel unfair.
Everybody who doesn't want to bother, well, eh, should avoid this one.
Perhaps I should give this game thumbs down, but at core it's real good. I had fun.
Now, I also should mention that Back to Shop DLC, that has glitchy store page so you can't review it, is way too bugged. While it's good, few puzzles don't work properly anymore, official solutions will not do. So watch out, if you are planning to get it, then you will have to live with few unbeatable puzzles and not being able to access last 10 puzzles.