gMusic is a great app for listen to Google Play Music on a Windows device (including Windows RT) but the API isn’t official from Google so developers are not guaranteed the APIs will remain unchanged. Google deprecated the API gMusic was using so many of the features were broken. This update (2.2.15) aim to fix the problems with the API and while some feature don’t work the main music playing feature seem fine.
The app is free with an in-app purchase option to remove the adverts.
02/27/2014 – Version 2.2.15
[!] Google deprecated API which we were using. This update is the first part of changes. Some features are still broken. We are working to make it work again.