I'm having the similar issue as described here, but although the topic was resolved in the thread I can't see what was the solution:
I've installed the graphene mobile them and mobile smart plugin from the .zip archive I've downloaded with the theme purchase and both installations were successfully completed with no errors. However after the activation of the Smart Mobile plugin the site is loading empty page. (both desktop and mobile
When I've visited the themes page, I've noticed that there is a message at the bottom saying "The active theme is broken. Reverting to the default theme.
ERROR: Stylesheet is missing."
When I've deactivated the plugin again, I'm able to Activate the theme I'm using, i.e. a chile-theme of Graphene.