If you are like me and are playing on a Mac OS via Steam then you might have this error (v1.0.37.0):

Error: Video system failure
The system is unable to create a window on the monitor you've requested. The most likely cause of it, is that you've assigned a specific space for application in the dock or you manually moved the space. This is not yet supported. Please revert it back to "None". Application will be terminated.

Fix:
1. Go to ~/Documents (this is your user documents folder)
2. Open the Larian Studios folder
3. Open the Divinity Original Sin folder
4. Open the graphicSettings.lsx in TextEdit
5. Do a search for
Code
                <node id="ConfigEntry">
                    <attribute id="MapKey" value="Fullscreen" type="22" />
                    <attribute id="Type" value="0" type="5" />
                    <attribute id="Value" value="1" type="4" />
                </node>

7. Change the value of the 3rd attribute (id="Value") from 1 to 0. This will put the game in Windowed mode when you launch.
8. After it launches go to the Video settings and change the graphics from Windowed to Fake Fullscreen.