Hi @snowymo, could you kindly provide more details with respect to the issue. What exactly happens when you run the stream engine application? Which model of eye tracker are you using? Also, the version number of your IDE and system would be useful. Might also be an idea to test using the older Core SDK to see if the issue truly lies with the Stream Engine API.
Something to also bear in mind is that if you are intending on developing an application for any use other than interaction (or gaming) which appears to be your intention to track gaze on a webpage, then you are legally required to purchase an analytical use licence from Tobii.
Further information about this @ https://developer.tobii.com/license-agreement/