The Canvas is the main window where you can edit models and create objects. Creating object is possible through the objects panel by drag&drop action.
Zooming and Scaling a Model
In the bottom right corner the zoom options can be found.
On the left hand side there is a zoom scroll that can be moved by dragging the dot on the line, or by pressing + or -.
The second icon is the Fit Area icon. After you click it, your model will zoom in or out in order to fit your screen. Using this icon gives you the full size view of your model.
On the right is the Scale to 100% icon. This icon brings your model to a default zoom factor of 100%.
Dragging and Dropping Objects
To add new objects to the model, drag&drop object from the object panel.
They will connect automatically to any existing, selected objects. If not, you can always connect two objects by clicking on one of the four dots at the end of one object, and then dragging that connection to the other object.
Creating a New Fragment
Select more than one object, right click on the one of those selected objects and when pop-up with icons appear, select last icon with title Create Fragment.
In the popup enter fragment name and click Save.
In the Fragments panel, you can see newly created fragment.