I hate to be the one to tell this, but unfortunately you missed the upgrade window.  Daz had a sale on Carrara 7 Pro upgrade going with a free upgrade to version 8.  You could try calling the sales at Daz to see if anything can be done, but they were pretty strong in there message about there not being an upgrade from 6 Pro once 8 Pro came out. It is still on sale right now which with the plat club discount is approx 65% off I believe.  But that ends tonight :(