Hello Tad,
Please create another forum post and we will look into it there. There can be several reasons which might prevent off-canvas menu to work. Can be cache issues, custom CSS issues, or so on.
It's difficult to give a solution without even having a look at the site. I hope you can understand.
Dave, we are sorry to hear that you had to roll back to the older version due to your deadline was knocking at the door. However, feel free to give us a buzz if you face anymore problems. Till then, you can close the post by accepting the most suitable answer so that others can find the solution easily as well.
Thanks!