Using cluster about gravizo

[TLmaK0]

Hi @MarcuSacramento. this should work:

digraph G {
	subgraph cluster_0 {
		style=filled;
		color=lightgrey;
		node [style=filled,color=white];
		a0 -> a1 -> a2 -> a3;
		label = "process %231";
	}
	subgraph cluster_1 {
		node [style=filled];
		b0 -> b1 -> b2 -> b3;
		label = "process %232";
		color=blue
	}
	start -> a0;
	start -> b0;
	a1 -> b3;
	b2 -> a3;
	a3 -> a0;
	a3 -> end;
	b3 -> end;
	start [shape=Mdiamond];
	end [shape=Msquare];
}

[TLmaK0]

you can use indirect way http://www.gravizo.com/#howto also