Sorry your Grandpa passed, goodluck with telling your mom. :( That's tough, man.
They're working on the update for 1.5_01 now so hopefully this afternoon. I don't think just redownloading the client would let you downgrade. You either have to get a copy of the 1.4 client from someone else or get a program that downgrades you. I'd just rather wait it out. Hopefully your client doesnt auto-update from here on out. I really think you're running a bootleg copy Art, too many suspicious circumstances.