How can I put the title and legend to a set of subplots (as a group, not to each one of them individually)? With the (old) pgraph library, a simple “draw” can do the trick.
You can add a title and legend for an entire set of subplots using the graphics editing features on the graphics page.
After you draw a graph (or reload a saved .plot file), you can create a title by adding a text box. Text boxes can be place at any location on the graph.
If you draw a legend for one of the subplots, you can relocate it to represent all of the plots. First right click on the legend and select "ungroup". This will allow you to move the legend independently from the subplot that it belongs to.