I can only see it live-no design mode is possible.
That is correct, there is nothing to see in design view.
Wordpress is made up of a number of different php files, and if you examine the index.php page you will see that it is just a collection of include files.
To give you a run-down of working with wordpress in Dw see -
Yes, I realize it's silly to think I can drag and drop with such a high level index file. Thank you for this, I honestly thought it was my mind going mad. I will
absorb these links.