Looks to me like it's a program that was used to rename SNES roms (SNESren[ame]) to their proper file name (based on headers, maybe??). Can't find much about it, though.
So I'm guessing this means that you need the rom "Super Mario World (U) [!].smc" which was determined to be that by the program SNESren v. 2.04
Why don't you just try checking the CRC32 or MD5 hash instead to make sure it matches?