For the speed, I would use plastic lattice fence sold at Home Depot. There are lots of different construction fences; some work well, some suck. Use lattice for the drop and construction fence only for the jump. The construction fence gives more grip for your takeoff.
For the yips that you're dealing with, make sure that you are dropping in a wider stance than what feels normal; about hip width or a little wider. On your ski in, bounce up and down a little. Don't actually get your skis off the ramp but simulate the popping movement a little. That should keep your legs a little looser. When you pop, make sure you are popping from both feet evenly. When you get 90 to the rail, extend your downhill arm out and down toward the far end of the rail. That will keep you from falling back uphill and also it would stop you from rotating past 90 on the rail.
If you think about all of these things when you are about to drop, you'll probably end up with your rail lodged in your ass. Pick one thing and think about it, take a deep breath and drop. These are the things that work for me, and my bruises don't go away as fast anymore.
If you are still freaked, there's one more trick. Imagine something really goofy and funny that you can get stuck in your mind. Imagine Tom Wallisch jumping onto a rail wearing pink fuzzy bunny slippers. It can be someone you know, but it has to be kind of weird and stupid; just something that will distract you from the rail.
Good luck and get it done.