Hi it seems so 
today i tried again and used instead of transforms saved in the part class, the nodes get actor forward.right and up vector and then multiply those by float variables from the part class which make in groups of 3 (x y z) the offset locations. It works on any rotation i tried so far.
Because the offsets get now recalculated every time a compatible part is traced the offsets no longer need to be adjusted Also the rotation is taken from the traced part and the player input rotation is added…
But thanks for that hint with the “rotate vector” node that will be usefull in other cases 
I added some screenshots in case someone is interested how i setted the new event up.
first the trace which gets the class of the old part and compares the classes and determines which set of snappoints is needed.
After that the snapsets get splitted up and the needed snappoint gets selected by another integer the player can choose.
On the last image you can see that the cubes now snap in the right offsets no matter which rotation the traced target actor has also the rotation is now correct and can also be adjusted .
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