Conflicting/Non-Responsive Buttons

CAPX: https://www.dropbox.com/s/8lcidl41effhkpx/Drift%20Star%20v0.1.capx?dl=0

I'm attempting to set up a lap racing game where drifting through turns is a must in order to get the best lap times. While I'm pretty close to getting a good balance of steering speed and drift recovery, I'm finding my controls don't always seem to respond... Namely that if I'm holding the D key before or at the same time I press the left/right key, I get no response from the car. This doesn't always seem to occur, but I can't quite nail why that happens at all. I'm not exactly sure what is the cause, either.

Could anyone point out to me what I'm missing and how I might work around this, please? Thanks.

There is actually some response, but just not that evident.

Since you are implementing your own Drift mechanics, why not try eliminating the in-built Drift controls by setting Drift Recovery for the Car behavior to 360.

necromaster - I shall give that a shot.

I think I've discovered part of the problem.

If I'm holding down the Up arrow key and the D key, my keyboard will respond when I next press the Right arrow key. But, while still holding Up and D, if I switch to Left, even after making sure the Right arrow key is released, the car won't turn left until I release any other key I have depressed.