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With that we have the angular velocities in the inertial frame. To get the angles, we only need to integrate the velocities. Since we only want values between 0° and 360° (or, as I luckily found out without actually trying, between -180° and 180°, which is much better), we divide the value modulo 360. Now we have happy little angles (in degree) which we convert to radians, to use them in Ptolemy.
Update: The same mistake with the same correction applies here as well. Look into acceleration to see further details.