Moving Digital Certificate with Private Key
 

I have recently gotten a new computer which I use to write/edit macros. My
old computer contains my original SelfCert Digital Certificate and Privat
Key. I would like to move these to the new computer so that the 100 or so
different files I have macros in can be editted on this new machine. I have
exported and imported the Certificate but the "export private key" radio
button is always grayed out or I get the error that this private key is
marked as unexportable. I have read many articles including this one
http://support.microsoft.com/default.aspx/kb/232154 about how to do this but
none have worked. This seems like a simple thing and I assume I am just
overlooking something. I do not want to create a new Certificate because then
everytime I edit a macro (mainly in Excel), I will have to resign it and the
users will have to set up this new Certificate.
If, for some reason, this is not possible, is there a way to write code to
change all the current certificates over to a new certificate that I would
have to make?
Can any one help me here?