For the moving stars I'ld need a better description of what you want. Should the stars be moving with the player, or should they appear to stay in place? Are they moving at the same speed as the player, or are you after some sort of parallax effect? Note that I've not played the games you mentioned.

As for the second question, easily done. First, establish a pointer to the player entity. Then, in the action for a planet, update it's position like so every frame:

my.x = player.x;
my.y = player.y;
my.z = player.z;

-Joe Hocking
www.3darteest.com