I've set up a blog at http://www.debbiewaller.com/hypnotherapyblog

I've created a category for blog articles and a couple of articles to work with whilst setting things up. The intro text is appearing but thumbnail images are not appearing.
I've inserted the images in the articles using the insert image button in the content pane, I have also tried using the images and links page but it doesn't make any difference.

I've read other posts about similar problems on this forum but don't really understand the answers, so I would appreciate some advice.