If anybody is getting troubles to access the game after an update, it should be solved in one of these steps:

1- Look into your browser options and clear the browser cache.
2- Close your browser and re-open. Login again at facebook and access the game with a fresh session.
3- If none of above worked, go to your facebook settings, security options, and disable secure (https) browsing. Try re-enabling again later to see if it works again.
4- If none of above worked, try with a different browser and starts again from step 1.