For other potential users - it turns out that two of the .dll files for the MATLAB server were not included with the v3.1 zip file. Just download the v3.0 zip file and copy these across. Worked for me.
I am attempting to use a recently purchased 4C. The Tobii software runs fine and calibrates, however The most recent toolbox (TobiiMatlabToolbox3.1 - EyeX SDK.zip) fails to connect when running the experimental suite. I receive the following error: Warning: Unsuccessful read: The specified amount of data was not returned within the Timeout period. SUCCESS: The process "cmd.exe" with PID 3852 has been terminated. SUCCESS: The process "cmd.exe" with PID 2588 has been terminated. I wasn't able to follow...