mrEkli
Yes i am, i've even changed the script in my 'intelxdk.config.additions.xml' to the following as shown on the shatter-box website where i got the plugin from -
<intelxdk:plugin intelxdk:name='https://github.com/cranberrygame/com.cranberrygame.phonegap.plugin.game#45191b3570a2ae4dc9646685b65f4a7994ed9952' intelxdk:value='https://github.com/cranberrygame/com.cranberrygame.phonegap.plugin.game#45191b3570a2ae4dc9646685b65f4a7994ed9952' >
<intelxdk:param intelxdk:name='APP_ID' intelxdk:value='YOUR_GOOGLE_PLAY_GAME_APP_ID' />
</intelxdk:plugin>
I've replaced 'YOUR_GOOGLE_PLAY_GAME_APP_ID' with my Google Play Games ID, although i've left 'APP_ID' as it is.