After having imported software from time machine, Aperture from the broken old imac is asking me to enter the key in new mac, but I don't have it as it was preinstalled in old one. I do have as a proof the serial number and date of buy of the original imac.
Aperture 3
Are you running MacOS 10.9 Mavericks and at least version 3 of Aperture? If so try running SW update to see if Aperture 3.5 is available. If it will install from SW Update it should solve your problem. Otherwise you either need to find the Aperture S/N that came with your old machine or contact AppleCare.
If updating does not work, as described by Thomas Emmerich, contact Apple for a replacement serial number, see:
Aperture software from a broken old imac is asking me to enter the key, in new mac, which i don't have as it was preinstalled in old one
