Some SF Symbols will not work when configuring the icon in Stream Deck Configuration panel (e.g. the symbol named lamp.desk).
It seems that the issue occurs when symbols are listed in the right hand sidebar of SF Symbols beta as having an availability of 3.0 or higher (e.g. below).
I have checked that all fonts are installed, and restarted the computer. I am running BTT version 3.842 and MacOS 12.5.1.
Chris