I am planning a port of that board. But that is on my back burner. Currently I am doing board design. I am going to sell a break out board for the IMU, a MEGA shield for the openCopter flight controller, and an all in one unit for the flight controller. It will also be porting multiWii and arduPilot to work with my hardware. My software auto-detects whether you are using SBUS, DSM2 or DSMx serial, or standard RC signals. But I digress. Here is why freeIMU, arduIMU, sparkfun razor IMU etc have so much trouble with yaw. Look at the datasheet for that compass:
Notice that it says nothing about layout considerations. Now look at this version on the bottom of page 5
They specifically say to not put any pour under that IC. All those people do that. I doubt that even full soft and hard iron calibration would take care of those problems. I also consider it to be lazy design to not have all of the axes point in the same direction for the chips. Please don't get me wrong I think very highly of everything 3DR ardupilot and freeIMU. They have done awesome work. That was just the one nitpicky thing I noticed.
Not to mention that there are tons of fields around which really mess with compasses. My boards will not have that defect. Also, my boards employ 2 3.3v regulators. One for the 3.3v IO and another for the 3.3v analog inputs to the ICs. This hopefully will mean that my boards will significantly outperform the other guys boards.
If you want to do a sketch using the openIMU on that board I will be happy to offer you any guidance needed and include your code in the code examples. Good luck. Keep me posted.