It doesn't contain all messages since I don't need them all but it would be very easy to add. Also, to keep things simpler, it will always write message headers so the output files are not optimized but they are functional.
-By popular request the FIT_SDK has been updated to support C#/.NET starting in version 5.00 (avail under the downloads section). FitGen now generates C# code and demo encode/decode apps are included.
Thank you so much! This is exactly what I needed. I was about to compile the java source files to a .class and then use IKVM.NET to convert the output to something usable in the net framework.