looked at the unit, but with no satisfactory result so far, the props rotate like they should but now when fading out they fly a bit longer than the bomber itself (with the original model first the props fade out and than the bomber, but even there not at the same time).
You can use the props form the standard one (this was what i did, there seems to be something broken - but i don´t know for sure - in the object or the nodes, eg the rotation of them was not the same, so i copied the entire object). In nifscope you can change the position of the individuell prop nodes to center them to the corresponding engine, at least here it works, the position is not reseted.
Btw how to you add damage stats, do you imitate the structure of a standard nif (both objects, use all controllers, rig the corresponding parts of the model to the nodes in the damage model,...)?
edit: attachment removed