My expierience with mirrored sites running java applets on 
Windows platforms:

Symptom: only grey-shaded applet area
Java console shows messages like this:
   
java.lang.illegalArgumentException
   at ...... (Unknown Source)

Reason: Browsers (IE,NS,..) are erroneous and therefore 
unable to handle correct path to java class files located 
at local disks (i.E: <file:///C:/>...).

Solution: Simplest circumvention is to install a local web 
server like apache (done within 5 minutes from 
<http://www.apachefriends.org/en/xampp-windows.html>; 
download the XAMPP lite version, unzip, start& use it), 
then you can refer to your mirrored site 
by //localhost/mirrored_subdir/...
or by redirecting mirrored web addresses via alias 
definitions to any local directory