Ever since iTunes 12.2.0.145 upgrade, Garageband won't share to iTunes

Hardware: Macbook Pro 13"

OS: 10.10.3

Software: iTunes 12.2.0.145, Garageband 10.0.3

I've been spending my weekend merging together 10 minute samples of music 9 at a time to make 90 minute tracks in garageband and sharing them to iTunes as I go.

When I tried to pick up where I left off after upgrading to 12.2.0.145, all of a sudden when I try to share from garageband, it goes through the bouncing and the normalizing, and the converting to AAC. But then instead of the track appearing in iTunes, Garageband quits and generates an error report:

Application Specific Information:

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSCFString rangeOfString:options:range:locale:]: Range {17521921, 512} out of bounds; string length 17521997'

terminating with uncaught exception of type NSException

abort() called

(Plus hundreds of more lines - too much to c/p.)

This sounds like a garageband problem, but it only started happening after the iTunes upgrade. Compatibility issue? Is there a workaround? Is there a procedure to report this to Apple so they can fix the glitch?

In the meantime, I need this for a project due tomorrow night. Any suggestions?