I've finally found a copy of the first issue in the Femdom Compendium series by Swish Publications. Very similar content to Madame, but longer stories and no letters.
You can see the cover galleries of each issue here - https://swishpublications.wixsite.com/swish/femdom-compendiums
As far as I know there were only seven in the series which are all now available as PDFs.
