Special keyboard keys

I have a logitech keyboard with the windows "application key" and a "Fn" key.
If I try to remap them, BTT doesn't show any keypress for them.
Is this a bug? Or is there a workaround?

--jason

on many keyboards the fn key is only used internally and not forwarded to the system at all..
However BTT is not a key remappings tool. You can try Karabiner Elements instead.