I was trying to implement this code (unfortunately, the website is down, so I had to dig in the Internet archive).
I get an error in RenderDot function:
PInvokeStackImbalance was detected
Message: A call to PInvoke function 'testing_graphs!testing_graphs.Graphviz::agmemread'
has unbalanced the stack. This is likely because the managed PInvoke signature does
not match the unmanaged target signature. Check that the calling convention
and parameters of the PInvoke signature match the target unmanaged signature.
What to do? There was a sample app here - maybe someone has it?