Jenni: Yeah. I'm on Yosemite 10.10.1. I haven't been able to switch the sound though, even in the sound settings, so it looks like there is something going on with this on Macs (since it only plays through my Mac speakers and won't let me switch to output through HDMI).

I'll post a bug post on the Double Fine forum later today about it (once the bug fix forum goes live), but if you want to try asking on the Grim Fandango section of the Double Fine forums about it before I do, by all means feel free.