I can report this on github but this might be just as fast. I was trying to track down why my C++ port was driving differently than AOG. Was affecting both my turning rate and also my lookahead values. Turns out that I had the setting isRollFromAutoSteer enabled, but of course I didn’t have any roll values coming in from the simulator so the roll in ahrs.rollX16 was set to 9999.
But in the code I translated from Classes/CNMEA.cs, line 229 (in UpdateNorthingEast()), I noticed that the if statement does not check to see that ahrs.rollX16 is != 9999. Hence my code was getting a really wonky roll angle. After adding that check (similar to the code in OpenGL.Designer.cs that draws the roll bar), things seemed to work a lot better, and more like AOG (unless of course you turn on roll from autosteer while using the sim).
Hope this makes sense. I can put together a pull request for AOG if you want me to.