I don't know about BTT, but when I got my Stream Deck (in my case, just the mobile software version) it took me an hour to realize I had to choose between the built-in Stream Deck actions, or the Keyboard Maestro action (which you have to figure out how to download from the Elgato marketplace.)
There are now two choices when it comes to downloading a plug-in from the Elgato Marketplace to make your Stream Deck work with KM. One is called "Keyboard Maestro" and the other is called "KMLink." For a discussion about which one may be best for you, here is a thread discussing the choices. The former seems to focus on power, the latter seems to focus on convenience. I prefer the former.