If you are looking for a registration code to remove reminders or unlock all features, the developer (Rene-Gilles Deberdt) has provided the following updates on the Official Cyna Games Site No Direct Sales:
If you can’t find a legitimate copy of Kyodai Mahjongg 2006, try these legal and often free alternatives: kyodai mahjongg 2006 registration code
Some versions of Kyodai Mahjongg 2006 used an algorithm that tied the code to your computer’s hard drive serial number or network MAC address. This means a code that worked on one PC in 2006 may fail on a modern laptop. If you are looking for a registration code
: One of the most famous aspects of the Kyodai Mahjongg license was the promise of "free upgrades forever." Customers who bought the game as far back as 1997 were eligible to upgrade to the 2006 version at no additional cost. Technical Compatibility Technical Compatibility If you search for "free registration
If you search for "free registration codes" or "cracks" for this game, you'll find plenty of shady sites claiming to have them. Security Risks: