Wolfgang, thank you very much for your answer about placing text.
Using:
\startplacefigure[location=force,title={First dummy caption}]
\inmargin{First margin dummy}
\externalfigure[dummy][width=\textwidth]
\stopplacefigure
The text in the \inmargin section appears at the bottom of the figure. This works for about one line of text. For some of the figures I'm trying to put 3-4 lines in a wide margin and would like the text to appear at the top or the middle of the figure.
I asked a question over at Stackexchange on this:
Using \starthanging \stophanging put the text in the correct place but then the figures ran into each other.
regards
Pete