boeing247 wrote on Nov 4^th, 2012 at 11:43pm:

The NavData for Captain Sim products can be found in [MSFSX Directory]\Captain_Sim\navigation. I've never taken a look at the files themselves for CS, but I have edited the files from another developer to add an airport that wasn't included. There's a specific format you have to follow to add information on each airport or waypoint that you insert. The latest AIRAC cycle is always available on Navigraph for just a few dollars.

I fond the files but there all in dll format :(