If you're seeing the force close message, your solution for now is to revert back to the previous Google Play Music version 7.9.4918.If Play Music is a system app on your device, you'll probably have to disable it to revert to the original version that comes with your phone, then manually install v7.9.4918 by downloading the APK file from APK Mirror.
Set up your account The first thing you'll need to do, even before downloading the app, is set up your Google Music account.
If that trick doesn’t work, then maybe you need to update your Google Play Music app first.
You can grab the newest version here (v6.7.2712Z.2783167).
The feature will also introduce a nifty little mini player and let you download music from your library without installing the Music Manager.
Since it’s a Labs project, expect this feature to have a short shelf life unless Google chooses to stick with it.