You're better off getting a CIA and using makerom.exe to convert it to CCI, then Using 3DS ROM Tools GUI ( https://www.dropbox.com/s/y34za3admmxo3d...ls.7z?dl=0 ), Then once you've done that just chose the "Unpack ROMFS" option.
As far as 3D World's actual files go, dunno. Post a sample if you get it to work
As far as 3D World's actual files go, dunno. Post a sample if you get it to work