I was at the venue on the equivalent weekend last year for the European cross country championships (athletics) : the first part of this route is around the largely flat main parkland area that was the route for that. There is one steep sided mound (about 4:30 in the video) in that otherwise featureless zone: the equestrian area in the second part of the lap looks more interesting: it was behind the athletes' warm-up area last year, so I didn't really see it.
But I won't be watching, I'll be at the Euro Cross again, hoping my nephew can go one better than last year. But this year's cross country, in La Mondria park in Turin, looks like it would make a better cyclo-cross route than Abbotstown.