This problem is a problem with your computer. For whatever reason, there is a file missing from your computer. The game works for others because the file is not missing from their computers. This file is not part of the game, does not come with the game and should not come with the game.

This sounds like some other program installed on your PC is interfering with ScummVM, the program that is used to run Beneath a Steel Sky, possibly a virus scanner or external firewall. Pre-built PCs usually have crap like Norton's free trial installed, and that'll sometimes cause prompts to appear incorrectly while you're playing games (I know Comodo has this problem).
Be thankful. German keyboards have the Z key in the middle of the keyboard.

There's a file called setup.exe inside the game directory to redefine the controls, by the way.

I've never had any issues with GOG games on all my different machines.

If you are using UAC, install the games in a separate directory. Like C:\games. This avoids administrator issues.

If you have a problem with the newer titles, you should bring your query to the developers who actually made the game and understand it better. GOG support is more responsible for the games that involve dosbox emulation and for whom the developers often don't exist anymore.

@op

First of all - do you want to bitch about GOG/games etc., or do you want to play your games?

If second, you should start trying to do what people say in this thread. No install in Program Files. Second - use shortcuts to run your games, not exe files. It's because shortcuts contain compatibility settings.

I just installed Unmechanical + the update on my new Windows 8 laptop I bought last week, and I see no such issues with it. Works fine.

A couple of notes though:

- As some have suggested, I installed it outside of "Program Files" due to the issues it has with many older games. I installed it under C:/Games/GOG.com/ instead. However, since Unmechanical is a pretty new game, I think it should not have an issue being also under Program Files. As has been mentioned, GOG is indeed updating its game installers to install outside of Program Files by default. It is a valid complaint that GOG installers should install the games by default to a place where they should work at least in theory. The issue with old games/programs under "Program Files" came with Windows versions newer than XP, ie. Vista, Windows 7 and Windows 8.

- When I launched the game, my Windows firewall said that "udk.exe" wants to connect to internet for some reason. It is from Epic Games, so apparently it is some executable related to the Unreal engine that the game uses. I have no idea why it wanted to connect to internet, but I didn't allow it to, and that didn't affect the game.

Anyway, if the game refuses to work on your PC because your Windows installation is broken (you are missing some sound driver file?) and you are aggravated by it, unfortunately PC gaming just might not be for you. Have you considered a gaming console instead? It is a give and take: for all the freedom that PC gives you for choosing from all kinds of different configurations and price brackets, it also has more compatibility issues.

Honestly this is just PC gaming. You have to mess with stuff sometimes. If you can't stand it then play on consoles.

I understand how people who don't know much about computers can get frustrated when games don't work on their setups, but getting angry at people who are trying to help annoys me greatly.

Ultimately, this. Running old games on new computers is often particularly challenging.

On the plus side, this is a very friendly community and people will go out of their way to help you (as already demonstrated!) as long as you are prepared to help yourself, follow the suggestions given etc.

PC games have always been like this. In fact, they used to be much, much worse. In the early days of pc gaming, you had to expect at least a day or two of mucking around in your system files to get a game to work, doing things like memory management and irq conflict resolution. And there wasn't even an Internet back then to tell you how.

I am sorry you are frustrated, but I don't think you have to do much to get your system to work. Just follow the tips people have provided on this forum (install to a user created directory, and reinstall your sound drivers). Often times with a new computer, if you get one game to run, the rest will start working. You just need to work out a few kinks up front. I own hundreds of games on GoG, and so far every one of them has run just fine (including Unmechanical). I even have the exact same operating system as you.

Obviously you never had an old NES. :P

Actually that makes me wonder, would the OP mind telling us their age?

You are a saint but I think the OP has made it clear that if their is any adjustment to be made, even extremely minor, then the game is worthless.

Still I'll wait and see what happens.

Can I have your games :P TLDR. I am kidding of course, I'm am sorry that you are having any issues with your games. I really haven't had any issues with any of the 120+ games that I have bought here on GOG. You might want to contact support orgo to specified games forum, they're usually someone to help you along to get your game up and running.

Hi bill. If you won't be able to resolve your issues with a help of GOG staff, you can always try to ask them for refund.

Don't only try the help in the forum. Contact the customer support of GOG and let them know. Also include your specs. Maybe your computer is too old or runs an OS that has incompatibilities.

At least this is very unusual. For me GOG games usually work like a charm.