Using the quick start sample provided by Google I\'ve been able to get Sign In for Web Apps to work in Chrome and Firefox. However it fails on Internet Explorer (version 11.
While running in localhost, if you add Form Id to your form in Login page, it wont process after login through Google Login button. Even the Login status wont get changed to "Signed" on Google Login button. But this can be resolved by running the page on Public Server, since IE has feature to restrict scripts while running locally.