Hi ,
there is a blueprint node doing exactly what you need. I do not know the name by heart but if you put ‘inverse’ in your node browser search field you should get something like ‘get inverse transform vector’ or something like that. I am sure you will recognize the node I am talking about. There are two similar nodes, one for each direction of transformation. The tool tips will tell you which one to use. Just put in your angular velocity vector and your actor’s transform and you get your desired result.
I will add the correct node name as soon as I get home.
EDIT: As promised, the actual name of the node:
