Okay, now I see why Keith was talking about the movement lines in a recent email to me; the forums "helpfully" stopped emailing me about this thread, sigh. A few points:
1. The thing with the range not reaching quite all the way to your cursor is an oddity. Not sure what is up there. I think Keith was working on a fix for that, but it wasn't working with the waypoints as it stood.
2. The red section is denoting deceleration. Basically, if you want to END on the point you are at, the ship has to stop firing its thrusters at some point. The point where it turns red is where the engines cut off. Why is that relevant? Because if you move all the way to the end of your range, you will note that your red portion goes down, meaning that you will still be at a very high speed. So next turn you know you will have deceleration to deal with -- you can't stop on a dime -- since it wasn't accounted for this turn. If you are moving very far and see only a short red deceleration bit at the end, then you know you will be slowing but not fully slowed. Etc.
Despite being very confusing, the red is actually super informative. My thought was that a tutorial note would address that. How to explain that concisely is tricky, of course. Maybe not using the color red would also be good, since that makes it seem like an error area. I picked it just because it's high contrast. Doing something less high-contrast for #2 might make it so that it's still as useful for advanced play as it is now, without being surface-confusing to new folks or folks who have not read the above. Regarding #1, I think that's just a matter of it being a bit of a bug. I'm not sure how important that is to chase down instantly versus the other things on the plate, though.
One small thing. Are missiles meant to be able to be shot out of space? I had a few missiles on my tail, so thought I'd try to shoot them down, but I couldn't do it. I tried direct fire.
Depends on your weapon, but in general no. I believe the piercing shot does it, or concussive.