The dc_boot.bin file is region-specific. If you use a Japanese BIOS, Flycast will default to a Japanese menu and region settings unless you tweak the FlashROM. For maximum compatibility, advanced users often use a or "HKT-3030" BIOS, but for general use, the USA (NTSC-U) BIOS is the most stable.

Despite its technical success, the project faced a dark turn in 2025.