I still get the same problem of it not saving. I've tried using both Chrome and Firefox now :-/

Just to make sure we're doing the same thing. I added a RAW block to a page and then copy and pasted your code into the content box. However, once I hit save I still just get the spinning UNA symbol indefinitely :(

Is there some sort of permission that I might need to change do you think?

Thanks for your help! :)