The robot invader only speaks binary. You can't get him out of the cell. You need something from him and you'll have to find another way in. (see related question)
How do you talk to the girl in the hay loft at astro knights island?
Go to the guy in the green hood. Talk to him. He will give you the manure.
You don't defeat knights, you talk to them and they'll give you a weapon to defeat a beast. (On the jungle planet, find the Laser Lance down in the plants before you meet Sir Cador.)
You talk to the knights on different planets
Talk to the freckled guy with the spade. He's by the mill.
Talk to the head mechanic at Astrozone and get a new spaceship. Then you can go to the planets on the Queen's coordinate list (jungle, fire, and ice planets).
you can talk to her in the door on the bottom of the windmill . go in she will be on the top of the inside of the windmill
To get the space ship powered you need the bag of manure but it will crash on pewter moon, so you have to talk to the alien in the building if you can build a new one. but choose a fast but its has powerful shields, too.
Talk to the people in the secret hide-out.
a green guy has it talk to him and he will give you some
you go into the portal. then you go to the bottom and talk to the princess.
You go left until you reach the castle and then you go upstairs and talk to the queen. She should give you the coordinates. (they didn't really work for me, so i just looked at the map.)