How to downgrade installous 2.0.3 to 2.0.2?

ok i have the version 3.0 on my ipod touch 2G and i jailbroke it. when i add the source for hackulous everything goes fine but when i install installous it says download complete but when i return to the home screen all i see is cydia and not installous. i dont understand why installous is not showing up on the home screen. plz hlp!