merging pptx drops template

[Louis . Masters]

I just noticed that when I merged pptx files (creating a new pptx), the 
slide templates are gone.  The code I am using is basically:

XMLSlideShow newppt = new XMLSlideShow();
for(String ndx : deckIndexes) {
        int iNdx = Integer.parseInt(ndx);
        XSLFSlide slide = coreSlides[iNdx];
        if(slide!=null) {
                newppt.createSlide().importContent(slide);  //THIS IS THE 
CODE!!!
        }
}

I'm guessing I'm going to have to dip deeper into the slides, but I want 
to be 100% sure before I go down that road.

Thanks,
Lou