[Plugin: NextGEN Gallery] Adding Prev/Next Arrow Buttons

I followed the instructions in this thread to make it so that clicking on thumbnails will load respective images in a designated div. However, I’m now wondering if it’s possible to add prev/next arrow buttons to the div where the larger image will exist. Because I had to use a custom effect (as opposed to highslide or something like that) to make the larger div thing work, I can’t use any of the ones that have this feature built-in.