I am using Samplitude 11, in that I select the object that I want to duplicate and I press CTRL+D and it create another copy of the object, I can then move that object to a new source track.
But there is a lot of things going on you have to know about before getting the total grasp of this program, it isn't a program you can just use and understand.
For one thing, there are mouse modes. A mouse mode is where you can change the functionality that the mouse will provide while using it on an object or track. I am not sure what yours is defaulted to, I think it would be the universal mouse mode. That mode allows movement but you have to pay particular attention to where in the object/track you click. The upper part of the object/track has different functionality than the lower part.
This might seem combersom at first, but ideally once you understand the functionality, you will greatly appreciate the program... it truly is the best DAW I have ever used.