Hi again. I did download the Mesen core and info file. I can run the core from RetroArch, but the core is not an option the list (as shown in your picture) when I configure the emulator from LB. Perhaps I should have downloaded the Mesen core from within RetroArch, but there I had only the standard NES cores to pick form. So I downloaded them manually and placed it in the core folder. BTW regarding your previous reply on the Nestopia code, I do not have a NstDatabase.xml under my systems folder.