deployment credentials on a Azure based WordPress site

I am new to WordPress (and Azure). I am following these instructions :

http://www.windowsazure.com/en-us/develop/training-kit/hol-webappgalleryazurewebsites-osx/

I try to upload files using the deployment credentials. I can see the site files but have no write rights. I have no idea how the deployment credentials in Azure relate to users or file authorizations in WordPress. Can somebody please explain how this works? Thanks!

p.s. my site is http://www.nedphoto.nl