I can see potential with this game so I'm leaving a little feedback.
-When clicking on "Instruction" on the main menu, the sonic void sprite remains visible
-The select level button goes to the first level
-After completing a play through, the instruction button loads a test scene and then goes to the 1st level
-Spacebar skips to the next level
-For webplayer games, don't use the right mouse button (it brings up the webplayer options)
-Hit detection on objects that are far away doesn't work
-Enemy ships are difficult to spot until they are too close
-Once they are behind me I can't shoot them and they just ram my ship
-The bullets don't go where the crosshairs are the farther away from the ship it is
-Enemies don't seem to die
-If they do die they turn pink
-Enemy bullets don't really look like bullets
-The floating bluish cubes are not explained and don't do anything it seems except clutter the level
Keep at it and update the game as more people review and I think it'll turn out ok.