This patch allows each individual (vanilla) dragon coin to be saved once it's collected. Unlike the other method, you don't need to replace all dragon coins with 5 different custom objects for every level.
Read more info in the dcsave.asm.
JackEdit: Added option for only saving when the midway point is collected (needs 8 bytes of freeram more) and to disable the transparent blocks if you'd rather have them not appear at all like the vanilla game.
worldpeace edit: removed the redundant code which made this patch incompatible with uberasm