if the horse are running through the fences try creating a race in the race builder, watch them jump a fence then go back and try watching the league races, worked for me.

I can run the UK races fine (probably because I did the commentary) but the US ones sends the game crashing back to the desktop. I know DB as tried with various settings, does Mark have any idea what could be causing this? Just a thought.

One of the mods, not sure which one, involves a reduced list of names for the US game. This might explain why the US races only are giving you grief, if you have that mod installed.