maybe it is a good idea for you to build a box and a rail. so you can practise new moves on the box which is less painfull to fall on then a rail and then do it on the rail when you have it locked. it is fairly easy to make look at my drawing on the link
so is it easy to swap the rail and the box, but they are secure in the ground so they won't fall over or something like that when you ride it.
if you have any questions or ideas feel free to ask/say.