Steps to reproduce the problem:

• create new course
• add new file (web site containing static web pages, images, css files...)
  I was using this one http://learningdesignpatterns.org/backups/depths.zip
• set index.html as main file
• backup and choose IMS CC
• validate through http://validator.imsglobal.org/cc/index.jsp?validate=cartridge
• restore the course

As the result I have only one page without any image or style applied. Other connected html files are not available.