The Status bar should help you working with the tool, for example by displaying short information when you move in a menu. Furthermore it provides information about the progress of longer processes, so that you are able to estimate the remaining waiting time.
On the right in the status bar you see the used memory of the application and the free capacity. If you click on the recycle bin, unused memory is set free and additional memory reserved.
Similarly to other working systems you can use the recycle bin to delete Model Elements. Drag the objects you want to delete from a tab onto the recycle bin.
