I have a 3D-model in the collada (.dae) format. Its a class hierarchy of pieces. All rotation modifiers and correct parenting have been applied to the model previous to starting animating. The model is in t-pose. If you want to take a look at it - here it is:
Once i start animating, everything seems to work as expected, i can set keys, make a first cycle. Then, in Animation view of a general blenderscene, if i click on a seemingly random piece of the model and apply a rotation, the same rotation is applied to all pieces, and to all piece positions depending on there parent.
The pieces look like a small planetary system, with the torso in the center.
Is this a bug, or do i use the rotation key system wrong? All rotations used are normal euler rotations. I will attach the blender files as another link: