I have Techtool Pro 4 and I purchased it when I got my iMac in 2005. Its current version appears to be 4.1.2 (although I could have sworn the version on the CD was 4.0.6 or something. Anyway, now that I am running Leopard, will this be compatable? The techtool pro website has an update for leopard, but it costs $25 or thereabout. THe eDrive did not work on this machine when I tried to boot from it. Could this be a sign that I need to upgrade? Thanks for any help!