Downloaded version. 

Ok, I clicked on the OK button on all the error messages and the page downloaded. I was able then to submit the tax return. I got a confirmation number and a CRA response Code 80 so it seems it's Ok. 

Is this a bug or it happens just to a few users? I am Ok now but just hoping no more users are getting the same error.

I think this is a bug and mentioned to customer support when I called. I hope they fix it as I am pretty sure going to happen to more users.