You're the winner. Clue explanations below, and of course its your turn now.
Clue #1 (The maze represents being lost, and stars represent space).
Clue #2 (The substance is the very fabric of the Universe, space-time. When the compound word is broken apart, space is in the altered song title, Lost Somewhere In Space, and time is in the original title, Caught Somewhere In Time.)
Einstein's theory of general relativity deals with particular substance that is a compound word, which when broken apart, one is a word in the altered song title, and the other a word in the original.
Clue #3 (Lost In Space is the series, and is in the lyrics to Speed Of Light)
In the lyrics of another Iron Maiden song is the name of a series, among other things, whose title is in the name of the altered song.
Bonus clue: Space-time is the compound word hinted at in clue 2. One part is in the original song title, the other part in the altered song title. (Same explanation as clue 2).
Clue #4n (This is the robot from lost in Space, otherwise known as B-9)
Incorrect Guesses: Startrek, Starfind, Mazerunner, Star Somewhere In Space, Caught Somewhere In Stars, Lost Some Star In Space, Caught Some Space In Time, Caught somewhere in Stars