I'm using v26 and am having a helluva a time trying to select boundaries. I want to do this part in sections and I followed videos on boundary selection but BC seems to be ignoring what I select. For example look at my screen shot titled geometry,I want the tool just to do the selected parts, yet it generates toolpath for the whole dam thing. I also select a boundary see boundary pic because I don't want the tool cutting on the top because it's a mold. I've tried extracting edges for wire frames, using the wire frame to select the boundary, going around trying all sorts of combinations clicking on geometry sections, which is a tedious time consuming PITA, particularly when it just ignores what you select.

Is there some way to do this when you actually select sections of geometry, it does just those sections and nothing else? The latest video I'm following is this one.

https://www.youtube.com/watch?v=2mEKPYmnee8