The changes:
# Show "Free Play" instead of "Credit 0"
0x03AAC2 = 0x4652454520504c4159 ("Free Play")
0x024A54 = 0x4E714E714E714E71 (nop nop nop nop)
0x024A66 = 0x4E714E714E71 (nop nop nop)
0x024A74 = 0x4E714E714E714E71 (nop nop nop nop
# Flash "1 or 2 Player Start" instead of "Insert Coin" at Title
0x00576C = 0x600008DC (bra.w +0x8DC)
0x00604E = 4E714E71 (nop nop)
# Coin insert doesn't reset title screen
0x0055E0 = 0x4E71 (nop)
# Coin insert doesn't transition from story -> title
0x02C21A = 0x6012 (bra.s +0x12)
# Game start doesn't subtract coin(s)
0x024A20 = 0x4282 (clr.l d2; d2 is cost argument)
# Skip credit check at title/high score
0x0055F4 = 0x602C (bra.s +0x2C game start @ 0x5622)
0x005606 = 0x4E714E71 (nop nop)
# Skip credit check during demo screen
0x02EEE2 = 0x600000B4 (bra.w +0xB4)
0x02EEF0 = 0x600000C4 (bra.w +0xC4)
# Skip credit check during story
0x02C240 = 0x600000E2 (bra.w +0xE2)
0x02C254 = 0x4E714E71 (nop nop)
# Display 1 or 2 players start instead of Insert Coin (center)
0x02EE4C = 0x60000128 (bra.w +0x0128 game start @ 0x2EF76)