This is not that uncommon - one thing to confirm & then two things to try. On your MAC confirm that you can access the Internet ( you would be surprised how many times this is the problem, proxy's for Corporate Access etc ). If you can see the Internet, Open CWS 5 Right Click a Job & Impose to activate the Activation Wizard let it do its hunt & when it returns with "Licence already activated" message - hopefully you will see a question mark within a blue circle ? click on that - within that webpage you should have a link to "Restore Previously Activated Options on this Computer" - if this does not work - dig out your LAC ( Licence Activation Code ) which would have been supplied with the Fiery Software Disks & contact EFI support - give them the code & they can reset it on their Server - you should then be able to reactivate.
Remember you are what you eat ! I'm a twix..