OK so listen up... I just figured it out how it works !!
Example Serial Key : PH200907319FCB0C
PH - Philipenne Country
2009 - Year
07 - Month
31 - Day
FCB0C - A code given from Garena for a specifically Cafe.
PH - 2009 - 07 - 31
PH - Cafe is from Philipinne
2009-07-31 is the date when they registered & activated their CIG ( gold membership ) for their cafe....
But
the problem is ... We need the registration date of a cafee and it`s
country... and we can try combine it ... for Example : We know the date
& country .... RO20090802 ... and we add this code we know FCB0C
... and we get RO20090802FCB0C
This is just a suppose !!! You can try it out ... and reply us if it`s working.