I'm not sure what it is exactly. I've set it to "Ask Siri" in BTT, but when I push it, it doesn't work. With BTT focused, I get an invalid blip. In other applications, nothing happens. Assigning it a different action is the same non-functional behavior. On the other hand, when I push F4, which I've also set to "Ask Siri" (for now), it works. See the left side of the screenshot for what I've assigned F4 and F5.
Speaking of F4, I'd actually like it to be a shortcut for Spotlight, which reflects the Mac's internal keyboard. I've got it set to Siri to mitigate Problem #1, but I couldn't set it to Spotlight anyway because I can't find the Spotlight Action in BTT. See the right side of the screenshot - the search turns up empty.
I'm not sure I understand your first point - are you saying that the only option is to set the Spotlight keyboard shortcut in the System Settings app? I like having the system shortcut set to CMD+Space which is the default - what I'm trying to do more specifically is map my external keyboard's F5 key to mirror the internal keyboard's Spotlight key, which is F5.
no, one of the most important functionalities of BTT is the possibility to send arbitrary shortcuts to the system. Any trigger in BTT can do that. So in yout case you'd set F5 to send the cmd+space shortcut to the system - thereby triggering Spotlight
Ahh gotcha! Thanks for explaining that. Okay, so that's resolved and setup. Now I still have the other problem - F5 just doesn't do anything. In BTT, it just beeps. In other apps, including Finder, just nothing at all. I downloaded Keyboard Detective to see if any other apps were using F5, and I checked all my open application's keyboard shortcut lists as well as MacOS, and I couldn't find anything!
Any advice on how I can figure out what's going on with this key?