None of the computers on Arturus work because there's no power for them.
You do not get or use a bucket on Astro Knights Island.
It goes to the mud swamp, which is the only place that you can use it.
The gold coin in Astro-knights is in the fountain. You will see something glittering in the water, and if you pick it up, it will be the coin. Use it to pay your admission to the Mordred museum.
The small key in Astro Knights Island is for Mordred's secret hideout. When you come to that wind mill area, move the hay bales apart and use the key on that.
What you do is when you go up into space you click on the coordinates and you follow tem
yu dont yu get manure and use it tu get accross
use the rope and tjhe code dh h husfvbsufhsuiecdfhf
You use it to power the hover board (hovercraft) in the attic of the windmill. (see related question)
Since Mordred / Binary Bard only appears in the pre-recorded scenes of Astro Knights Island, you can't use the Costumizer. You may locate someone on the islands who copied the Bard when he was promoting the island in May 2009.
Go to the fountin and click on the souler system panel and enter the code
you get the fuel rod and enter the coordinates then you go to astrozone and ask the alien to use a ship
When repaired, the saucer will only get you as far as the Pewter Moon (X-56 Y-52). There you can get a new spaceship, and use the coordinates from the Queen's list or the onboard computer.