Glad it helps! It's not so much turning my shoulder. I'm still lowering to the same spot on my shoulder. But my body torques or twists as I'm going through the roll.
Good thing it's not the pain! That's what most people struggle with, so consider yourself a lucky one!
Your direction problem is pretty easy to fix. Focus on pushing off the back foot, and directing your roll straight ahead. It's when we lose that acceleration from our back foot that we lose control of our direction, due to our bodies rolling at an angle. As long as you push off that back good, visualizing a straight line infront of you, you'll start to straighten it out. But keep practicing, because you'll have to overcome your muscle memory.
As for rolling from a stand, it's no different! You simply tuck your legs in at the right time, instead of having the luxury of them already being tucked in, from a crouched position. Nothing else changes. Start working on it, because from a standing position is how you will mostly be rolling, in the execution part of your Parkour training.