This page details the winning mods and plugins from the complex NPC Retexture Merge. The Winning Mod Assets column shows which mod the winning texture came from (left pane of Mod Organizer), while the Winning Mod Plugin column shows the name of the actual plugin file (right pane of Mod Organizer). This will help users who want to create their own NPC merge using different face textures, and will also help troubleshoot the infamous black face bug. The main thing to remember in avoiding black face bugs is that the assets must match the plugin. If they don't you will get the black face bug.
Wartortle has created a spreadsheet to aid Troubleshoot you can download that Here