I am experiencing a similar issue. However it is limited in which elements can be added where. For example, I am able to add a countdown timer, but I cannot add any other element to my blog post (for example expanded quotes). 

This makes me believe it's not a blanket elements issue, although most of the elements are not working in my case. I experienced the same issue where the elements could be placed in the header, but nowhere else.

Any progress ?

Hi, I am having the same problem. Could anyone solve the issue?

Hi. I am experiencing something similar. I was using the website builder and suddenly drag and drop doesn't work and clicking on any block no longer shows the customize panel. Also, the footer on that page seems to have disappeared. When I edit other pages, it works like normal with the footer present in the other pages.