#12772, "RE: So I finally got around to doing my t-belt and..." In response to In response to 4
IMO squealing is caused only by the accessory belts. The timing belt can't really squeal, it would just chunk and shred.
I bet the reason for the timing belt getting scored is that a little piece of plastic broke off and fell down inside your timing belt cover. Check all the plastic standoffs and screws that hold it together. Or just destroy it, and leave it off.