try making the horse work when he misbehaves. Like if he won't pick up his feet send him in circles, back him up. Not in a nasty way just so he sees who runs the place! Lol! Hen try it again. If he gives it to you give him lots of loves and let him stand. If he doesn't give it make him work more. This everything. The way a horse thinks is "What is the easiest way to go about this." They like the easy way out of everything. Making them work makes them think of an easier way out. Example:
Your horse refuses to enter the trailer. Work him in circles then send him into the trailer. If he refuses keep him going. When he finally gets in let him stand and relax. Praise him and give him lots of loves! Then take him out walk him around the try to load again. If he doesn't then send him in circles again.
That was just an example but you can probably get what I mean. Lol! And keep in mind ~Its Never The Horses Fault!~ Something has been done to the horse, or the horse hasn't been worked with. Horses by nature are very trying animals and in the right condition will do anything for you if you treat them right! Good Luck! And its all about patience!