Help Understanding results of Offset Paths in Illustrator

[mrjackson]

I created this star with another shape inside it along with the and R which was converted to outlines. I knocked out the center shape  of the star with the Shape Builder.

I selected each shape and added a small "offset path" which gave me the images on the right.

If I wanted to add one more outline, but only to the outer outline, how do I do that. When I select the outer path, selected both new outlines. If I did the Offset Path command, it outlines outside the outer one and another on the inside of the smaller one. 

This is just a simple example, but I might need to add an outline around a graphic with dozens of elements. 

Do I have to find the sub-layer of the outlines to be able to isolate it to outline it?

[Bobby Henderson]

To create additional path offets the first offset path effect needs to be expanded. Be sure to preserve copies of the original paths to keep them from being consumed when the offset path effect is expanded.