If you select the Transmit Returns Now button, and it doesn't seem to be working, the most likely source of the problem is “cookies,” little pieces of code that are sent to your browser so we can personalize your experience.
What you should be seeing is a "captcha," screen, which helps prevent fraud by asking you to identify pictures before you can proceed.
If this does not work, you may need to Print and Mail your return. Instructions on where to mail your return will be printed out when you print your return.
I have had this same problem. I cannot get to the screen to submit, print or anything to do with filing. I have been stuck for over 24 hrs. and the problem has occurred on multiple device and browsers. Any idea on how to get from the review screen to the file screen.