Steve: I pasted your sample into WebGraphViz on my browser, then clicked Generate Graph!. The result was:
Warning: Not built with libexpat. Table formatting is not available in label of node a.
I don’t know if that image shows…I’m new around here and may have mucked this up…
At any rate, the upper bubble just said a : it didn’t have any of your formatting.
I did some more experimenting in another diagram, taking a box with a label and replacing the " . . ." with < . . . >, as specified in the html-label documentation. (There were no special characters inside the label.) Various things went wrong, but I don’t think it would be enlightening to describe them.
Finally, I inserted you “a” line of text into my own diagram. It just added an a with an elllipse aroud it to a spot in the diagram, and gave the same warning that you got.
I’ll be grateful for any suggestions about what the next step should be.
Thanks for your help with this.