The dlight images are different JK2 uses q3 method, JKA uses an external image. G2 API code has some various differences, JK2 doesn't support asian fonts and has some simpler font rendering. The JK2 Skeleton is used without the warning messages. JK2 doesn't support _off surfaces JK2 Strip SP_* Language JK2 has only 4 frustum planes and 5 in JKA Some fog and surfacesprite differences (IE jk2 doesn't have the global world fog definitions)