David:
Very, very thanks for the two mails.
I study both, as I run Mac "old Style" , and know little of Unix.
What drives me to this adventure is magic spell by Dominique Dubois about
send parameters to external code for having the output file of GraphViz as
input of Squeak.
I do several test with both types of VM, the Andreas Unix one and  several
of John Mac.
Using Unix VM lets do all trip and have the .txt file for parsing on Squeak.
Using Mac VMs, you must have GraphViz running or not work.

I have VMMaker loaded in my working 3.7 image, but said the pluggins is
missed and I don't know where the sources for compile are.

Again , very , very thanks and soon I bother you with more questions.
And no hesitate to send any thing what you wish test on Mac.

By the way , all this history is for me wish have a real road map of classes
in Squeak.
The Morphic-Basic.jpg resulting is 2.7 mb , have about 15000 * 10000 pixels
and take a while to open in external programs

Edgar