Fill the box with the text you want to appear in the node, then use the Literal or Resource buttons for a rectangle or an Ellipse, then drag the created node to where you want it. To connect two nodes, you again enter the text in the box and shift + click the from node then shift+click the too node. This is all extremely slow at the moment, so to look at what a completed graph might look like, there is an for you.
To view the triples of the graph - use the Output Triples button to get them listed below the graph in NTriple format.
You can also import XML+RDF to create a messy graph
Comments to email@example.com - Currently tested on IE5.5 with the Adobe SVG 3.0 plugin (it does not work with the Adobe SVG 2.0 plugin - I would like to get it working in others, but would need to get the Adobe Plugin working in them here first.