There is no direct integration with Google Docs and even those documents stored there and shared publicly do not embed reliably with their viewer (ironically), so at this time that use is not supported by the plug-in.
Based on my testing, Google has been 100% perfect however your plugin has caused me hours of problems.
First time it made the entire posts content hidden
Second time it simply didn't display anything
Never had a problem hosting content on Google Docs and displaying it in WordPress.
My advice is to upload your content directly to Google Docs and embed using Google Docs code.