This error comes with an warning:

• error:

  No such attribute for array(7): image
  Choose one of following: name, short_name, short_description, description,
                           show_children, tags, publish_date
  

• warning:

  Warning: eZTemplate:attribute_view_gui @ extension/ezflow/design/ezflow/override/templates/block/main_story1.tpl:7[8] 	Jun 26 2013 10:24:46
  
  Parameter attribute is not an object
  

.

Steps to reproduce it:
1 - enable ezdebug and redirects
2 - login with "Admin" account into eZFlow
3 - create a folder named: "Test Folder"
4 - edit front page
5 - add a new block of type: "Main Story (manual)"
6 - add "Test Folder" to that Block
7 - "end for publishing" 
8 - Verify error and warning on eZDebug