I have a dual NavNet 3D MFD system. One of my MFDs went down so I found a used one online and installed it on my boat. I made it the master and changed the previous master to slave. I imported my points and routes onto the "new" MFD and everything is working well except on each power up, I get the message that says my charts be unusable after 20 (decrements each time) power ups. I have the original chart and SAT data (sd cards) and unlock code for the original MFD. Do I import these charts onto the "new" MFD and if so, how is this done? Thanks, Rob