I did not like using external utilities but it is necessary for a gamepad controlled enviroment. Now
I am in love with JoyToKey and my 360 gamepad in my living room pc.
This guide is for a Chaos Domain profile. On a 360 gamepad it makes Y behave as Enter and dpad as WASD.

You need a text editor, like notepad, and JoyToKey, which is available at official page[joytokey.net]. There is no installer, just unzip and run the program to create an empty profile. Open notepad, paste the script below and save as "CDomain.cfg" in the same folder as JoyToKey. Your game now has full controller support.

[General]
FileVersion=56
NumberOfJoysticks=1
NumberOfButtons=4
DisplayMode=1
UseDiagonalInput=0
UsePOV8Way=0
Threshold=20
Threshold2=20
KeySendMode=0
SoundFile=

[Joystick 1]
POV1-1=1, 57:00:00:00, 0.000, 0, 0 ##Look up
POV1-3=1, 44:00:00:00, 0.000, 0, 0 ##Move right
POV1-5=1, 53:00:00:00, 0.000, 0, 0 ##Duck
POV1-7=1, 41:00:00:00, 0.000, 0, 0 ##Move left
Button04=1, 0D:00:00:00, 0.000, 0, 0 ##Shop

You do not want your gamepad to behave like that all the time, so you need to tell JoyToKey to switch profiles automatically. Go to Settings, Associate profiles with applications. Click "Specify a default profile" and select an empty one, like the default. Now your gamepad will behave normally
outside of Chaos Domain.
Click on "Add". "Application Name" does not matter, "Chaos Domain" is fine.
In "applcation path" you must enter the game's exe path, which is something like "C:\Program Files(x86)\Steam\steamapps\common\Chaos Domain\Binaries\Win32\CDGame.exe".
In "Associated Profile" specify the one you created before, which in my example is CDomain. Now your profile loads automatically when you play.

Steam Big Picture has essentially turned my PC into a very powerfull console while gaming. Until
SteamOS overcomes Windows, an external utility is needed to control the operating system with a
gamepad. I prefer JoyToKey because it switches profiles automatically. I have an empty profile (very
imprortant), a generic one for navigating Windows, one for browsing the Internet and one for every
game that does not have full controller support.
I chose JoyToKey but I am always open to suggestions. The guide is not totally noob friendly (no
pictures!) because I think it is clear enough but I can provide clarifications if needed.

I recently switched to Antimicro. It is open source and more promising than any commercial software
<?xml version="1.0" encoding="UTF-8"?>
<gamecontroller configversion="14" appversion="2.10.1">
<!--The SDL name for a joystick is included for informational purposes only.-->
<sdlname>X360 Controller</sdlname>
<!--The GUID for a joystick is included for informational purposes only.-->
<guid>00000000000000000000000000000000</guid>
<names/>
<sets>
<set index="1">
<dpad index="1">
<dpadbutton index="8">
<slots>
<slot>
<code>0x41</code>
<mode>keyboard</mode>
</slot>
</slots>
</dpadbutton>
<dpadbutton index="4">
<slots>
<slot>
<code>0x53</code>
<mode>keyboard</mode>
</slot>
</slots>
</dpadbutton>
<dpadbutton index="1">
<slots>
<slot>
<code>0x57</code>
<mode>keyboard</mode>
</slot>
</slots>
</dpadbutton>
<dpadbutton index="2">
<slots>
<slot>
<code>0x44</code>
<mode>keyboard</mode>
</slot>
</slots>
</dpadbutton>
</dpad>
<button index="4">
<slots>
<slot>
<code>0x1000004</code>
<mode>keyboard</mode>
</slot>
</slots>
</button>
</set>
</sets>
</gamecontroller>