Create a Wordpress Child Template for our site to add stop/start next/prev buttons to slide-shows

We have a WordPress photography site on which we use slide-shows. However, these slide-shows cannot be stopped intuitively. The user must click on the auto-hiding thumbnails row in order to stop the slide-show which cannot be started anymore. The code for stop/start already exists inside (there is a Boolean variable for this) also there exists methods for Next/Prev images (the template which we use supports 'swipe' gestures for tablets which calls these Next/Prev). What we require is to surface/adapt this functionality outside to allow users to manually start/stop the slide-show through a button placed in middle-center. Also, they need a prev/next button in the top-left and top-right corners respectively. The desired layout is shown in the attached annotated screenshot. The buttons should auto-hide after a small timeout like the thumbnails row in the bottom of the screen (one can look at the code there and take/adapt it). We are at your disposition with any further details.