TSingleGraph 2 demo: non clickable objects

[kokkoras]

In the demo, when you set an object (from the objet properties dialog box) to be non-selectable/clickable there is no way to access the properties dialog again to alter the settings.

I know it's an implementation issue though and not a library bug.

[Kambiz]

That's a demo program!

I think I should add something in the menu to turn on selectable option of all objects.