Hi,
Good news. Finally I have migrated to QT 5.x version. QT 5.x compiled desktop client can be downloaded from demo page. Also QT 5.x compatible source code is available at https://github.com/LiveHelperChat/desktop. Compiled desktop clients can be found at demo page also or at https://github.com/LiveHelperChat/desktop-compiled.
Also it would be good if someone could test desktop client under https connection. New mac'os package also should be prepared in a few days, anyone who wants can compile it from souce code. Like it's 5.x compatible it should be very easy to do so.
Developing application takes a lot of time. You can support application by donating. There is no company behind this application and it takes away my free time. Every donation matters and does not matter how small it is!