with the command line: $ circo -Tpng -Ograph graph.dot
No plots are created and the following warning is give:
Warning: Could not load "/opt/local/lib/graphviz/libgvplugin_pango.6.dylib" - file not found
[ellson] Are you building from source, using macPorts perhaps?
Try "rm -rf /opt/local/lib/graphviz" followed by a fresh "make install"
What graphviz version do you have?