Are you referring to an old plugin that was called Custom Field Matrix? I ask because I found an older topic here that mentions it while searching. http://support.advancedcustomfields.com/forums/topic/custom-field-matrix-migrate-to-advanced-custom-fields/
I’m unfamiliar with this plugin or what matrix questions are or how they work. Can you explain a bit more about what you’re trying to do an maybe I can point you to a solution.
