Getting my slideshow to load on Apple TV

Forgive this probably obvious question. I’m a newbie to FM4. Just created a gorgeous slideshow about 27 minutes long. It’s great on my iMac but when watching on my HDTV, pictures load and then stop for 40 seconds or so, until they reload. Is my file too large for the TV? How do I load the whole slideshow so there won’t be these sporadic starts and stops. Is there a secret to the settings?

How do you play them on your AppleTV? As an AppleTV export video you exported and sent to iTunes? If streaming the stops, your network seems to be too slow for continuous streaming.