I have this problem aswell, I asked it afew posts ago.
We should write it on the "pfba" github for cpasjuste so he can fix, just in case he dosent see it here.
I had the opposite issue. I have all the spectrum games on my MicroSD and I couldn't see them.
I had to manually edit the config file and add the path with the games. There's also no way to only show the spectrum games, the only way to see them is to show all.
I don't think there's any keyboard emulation either, so I couldn't even start any spectrum games