Just a question and a request, if possible.
Question: what do you mean with "I've changed this and added some login credentials to the LightstreamerClient.Start method so that it should successfully connect to our Lightstreamer server". What login credentials? Are you talking about HTTP AUTH? Can I have a code snippet that shows how you did that? Are you running behind a proxy? Please note anyway that all this is outside the scope of our, very simple demo.
Request: Could I have a diff between the demo code and your changes, or alternatively, could you attach your code here?

Thanks