Mozilla does not allow web content to link to local files.

In order to use this site you will need to update the prefs.js file located in your personal profile directory.
(Ex. C:\Documents and Settings\your user name\Application Data\Mozilla\Profiles\default\0sea1sl0.slt\prefs.js)

If the following line does not exist in the file then add it: user_pref("security.checkloaduri", false);
If the line does exist but has a value of true then change it to false.

You will then need to close Firefox and reopen to apply the changes.

For more information click here.