I don’t have BFD, but I use Geist (also by Fxpansion), and found that it’s important to change to the midi channel that Fxpansion recommends for your set-up (map to trigger patterns, or engines, or scenes, or hits, and so on.) before you initiate the “create map from instrument” command. Then save the map, etc. I do occasionally have to re-load maps - but at least they’re unadulterated when I do this.