As far as I know Version 4 is no longer available from the store as the current version is Crazytalk 5. Is there a reason why you don't want to upgrade your OS to either XP or Vista. You will find it increasingly difficult to find new software that will work with the older OS's.
If you really want to stick with Windows 2000 then you could try contacting support to see if there is anything they can do but now would be perfect time to make that upgrade. Crazytalk 5 has many more powerful features than CT4.
You can use the link below to contact support if you wish to.
http://www.reallusion.com/CustomerSupport/User/QForm.aspx
Peter EdwardsForum Moderator
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