Problems when linking to images in a case study

In the case study of under.me, I inserted few images, but I get an error that only local problems are allowed.
The path to the image is http://drupal.org/files/Under.me%20by%20Bar%20Refaeli%20Navigation2.png - so it's local to drupal.org, but somewhere in the process of saving the node, the images are replaced by this error.

There's another inline image which does show. I had the same problem with it, and it "somehow" got fixed. I suspect it's something to do with spaces in the filename, as @silverwing fixed it by eliminating all spaces in the filename: http://drupal.org/files/Under.mebyBarRefaelicart.png.

My guess is that in the process of checking for local files the parser is not handling spaces right, and possibly other punctuations as well. This is usually not a problem in linking to files.

Can someone say what is the process of checking for local images?