A couple of things to keep in mind for this race:
1) The ride outside of the park is a bit bumpy, although I haven't ridden it in a couple of years so perhaps it's been paved. So keep in mind that it will not likely be an ultra smooth road.
2) The run inside the park has some little ups and downs, and doesn't have a whole lot of flat. Your run distance is not very far, but keep that in mind.
Otherwise, the venue is really nice, so have fun.