1.Update your video drivers!
In most cases, that is the issue.Intel[downloadcenter.intel.com]ATI[support.amd.com]NVidia[www.nvidia.co.uk]
(Usually not required, since they make such great drivers)
2.Try disabling Steam overlay
-Click on Steam and click on the "Settings" button. Click on the "In-Game Settings" tab.
-Uncheck the box next to "Enable Steam Community In-Game" and click OK.
3. If you have an NVidia video card, make sure the game starts on the NVidia GPU instead of the integrated GPU (usually Intel). You can do that from the NVidia Control Panel.
4.If it still crashes after that (1% of the cases), send an email at devteam (at) inthekillhouse.com with the file Documents\KillHouseGames\DoorKickers\log.txt and any .dmp files you can find there.
Our game uses OpenGL, which is much worse than DirectX in regards to drivers. Therefore our game may not work even if your next-gen DirectX game runs fine.