Just keep on doing what you're doing at the moment, then gradually move onto you being inside but with the screen door open so they can get in and out, build up to you being inside with the screen door closed, so they can get used to meowing to get let back in.

As for the in before dark, with all of mine, when they were younger, I used to physically call them before dusk, but when they were at the outside when I was outside stage, I'd physically pick them up and bring them in, telling them that they had to be inside before dinner. They also used to get fed after dark, so if they didn't come in they didn't get fed.