well never heard of "Zlib 1.dlb" but zlib or commonly zlib.dll is a tool set for opening zip files, and yes most emulators need it. Its always good to have zlib.dll handy most emulators need them so it wont hurt you to use google and type in "Zlib.dll" and put that in the emulator root folder. There may be a Zlib1.dll also. but no dll name has a space like that that I know of. So try the normal zdll.