To select several blocks, hold down the shift key and hold the left mouse click to draw a selection frame. The selected blocks will change to have the same colored frame.
When you have selected different blocks, various options are disponible. For example, you can move, copy/paste, delete all the selection. You can also right click on it and open a new menu, in which specific options for grouped blocks will appear. You can label all the selection, create a group (which you can name and give a color) and blackbox it, which is very useful if you want to create efficient and quick graph. More informations about blackboxing are disponible here : http://help.celestory.io/en/articles/3978841-open-a-graph.
Zoom button +
The zoom + button allows you to gradually zoom in on your graph.
Zoom button -
The zoom button - allows you to gradually zoom out in your graph.
Zooming in and zoomong out allow you to get a simple and detailed vision. The first one appears when you zoom out, and you will see that your graph switches to simplified view mode to get a better overview of your graph. The blocks are then composed only of their titles and keep the same color. The second one is when you zoom-in, and it will allows you to link one block to another, and to set different options.
Adjust view button
The Adjust View button allows you to refocus and zoom out as much as possible the view of your graph.