Can't get customs to work on Mac

As the title implies, I just got Rocksmith 2014 on Mac and I want to play customs, but whenever I try and launch one I just get stuck on the screen before the fretboard loads in. I can still play my bass and the blue waves come out of the speaker but no song.

RSInjector is in the correct folder, I was sent a custom that definitely works on other Macs, and I own Cherub Rock.