Resize images dynamically using wp built in functions - compatibility

Hi

I am using a theme that uses some code to resize images dynamically using wp built in functions.

However, when any level of user that I create cannot access/see any of the images that have been posted on the site - and it seems that it is due to this code.

The code can be seen here: http://wpquestions.com/user/discourseShow/id/1981/discourse_id/20

Is there a solution to this?

Thanks