The TkRotationComponentData Property adds rotations to things. It is using this Property that things like the rotating jetpack hologram gets its rotations in game.
The Property has the following form:
<Property value="TkRotationComponentData.xml">
<Property name="Speed" value="0.15" />
<Property name="Axis" value="Vector4f.xml">
<Property name="x" value="0.4" />
<Property name="y" value="1" />
<Property name="z" value="0" />
<Property name="t" value="0" />
</Property>
</Property>
The Properties here are pretty self explanatory. Speed is the speed at which the object rotates around the axis specified.
The y-axis is the vertical axis used in game, so to get something to rotate around just the y-axis, all other values within Axis would be set to 0. t is always 0 as it isn't used at all by the game.
Unfortunately this cannot be applied to planets to make them spin (we tried!)