Resource pack is not working. Remove every other resource pack from your mix. If that doesn't work, copy the "resources.zip" file from the map folder and copy to your and if you're playing multiplayer, your friend's resource packs folder and then select it. You can download the resource pack on it's own as well.
I don't think the map works properly. Make sure that you're running Minecraft 1.10.x. If there is so much lag, it could break any map, even if it's rare. If you're playing multiplayer, try to be close to each other. I could made a mistake even if I tried my best to make the map 100% multiplayer compatible. If you think you've found a bug, you can contact me.
Courses are too difficult! Give up your habit of sprinting with pressing W twice.
..what's happening? ...
Optional resource pack download in case if something goes wrong: https://goo.gl/dv9BQc