Unable to connect.

[uwejan]

Hello there,
i followed the readme, and the code from example, i keep getting the following error on app launch;
E/Receiver: .mqtt.connect-and-subscribe/500c1759-571c-4eba-aa3b-c77390439a5d exception
_2 how do i specify will topic, and will message?
_3 dose it support non ssl?
_4 dose it support websockets?
Thank you.