I experimented with an API but paused any development because of unclear legal situation with the upcoming EU copyright reform. MG does not provide data dumps. Currently it's possible for unicorn users to get a xml/json of modules and positions in their racks. I did that some time ago on user request but I am not sure if that is used by anyone so maybe that feature will also vanish eventually.

Beep, Bopp, Bleep: info@modulargrid.net