Problem with auto generated content

[jmarceli]

Following the 'making blog' tutorial at http://doc.locomotivecms.com/making-blog I encountered problem which I can't overcome. After placing http://doc.locomotivecms.com/making-blog/posts.yml inside data/posts.yml and executing bundle exec wagon push development --data I get an error featured_image => can't be blank. This error is caused by the url in the file field. When I put there valid file url (like images/1024x768.png) everything works fine. How to force locomotivecms to accept urls like it is shown in the tutorial?
I get similar error in data/photos.yml for the post: field (same message). In my file there is only one photo entry with post: afternoon-delight (I checked that localhost:8080/posts/afternoon-delight exists). If anyone could help me with this I would be very thankful.
Locomotivecms looks great. For now it looks like the CMS I was looking for.