Calculate local location (in BP)

Hi I’ve a Base BP and want to place a array of objects one besides previous one.
For that I’ve placed a child actor to get the first object location, I can’t get the right next position (I guess Child X world location + child Y vector)
But the result is not what I expected, the inconvenience is if I place the base object in different rotation in the world. Somebody could help me to set up the right way to set it up right in any rotation?

You’re almost there, it’s (X world location + Y offset) rotated by X world rotation. Use the “rotate vector” node for this.

Thank you for response, I show you what I’ve tried before but the result after offset is the same than with out it (I’ve checked in the outliner in Play and both has the same location).
Don’t mind the made vector for the Delta Location, if I put manually 0,10,0 (for example) the result is the same.
Something else when I press Stop the Unreal crashes (4.5.1), I’m not sure if is about that.