Raw data preprocessing

[Xen-R]

Hello.
I'm looking for some reference for comparison with my filter implementation.
I've got log files from betaflight (attached btfl_0012.01.csv) converted to csv file. I tried to apply EKF, Madgwick and Mahony filters to raw imu data (with dt parameter set as the difference between neighboring timestamps).
The results of filtering are not close to the real events happening during the flight. I assume that this can be caused by the lack of data preparation.
What is the right way to prepare data for filtering? Is there any other important things that should be taken into account?