Follow these rules, or bad things will happen! - Don't mix ROMs for different platforms - use generic BASIC with generic KERNAL, Mega65 BASIC with Mega65 KERNAL, etc. - Don't mix these ROMs with any other ROMs; exceptions: - kernal_hybrid.rom, which is meant to be used (and has to be used) with the original BASIC ROM; however, this hybrid ROM cannot be distributed due to legal/copyright reasons - chargen.rom - this one is fully interchangeable - Don't mix ROMs from different builds/versions (again, CHARGEN is an exception). - The generic ROM set should be compatible with any C64-compatible machine; platform-specific ROMs might not work on other platforms. Have fun!