You seem to be just making changes here and there, trying to get it to work. That will never get you finished. It is just making your code more fragmented and hard to read.
It appears that you are not clear what to do or how to do it. I recommend that you step a away from the code and work on the logic and the flow of the program. Maybe explain it to another person, how it will work.
It helps to talk out loud. Explain it to your dog if you have to. Once you are clear on exactly what you want to happen and how it will work, you can start coding. For instance, you need to answer some important questions.
When do you fire the dart? Where does it get fired from? or who fires it?
What happens when it hits the spaceship? What happens if it misses it? Does it disappear? Does it go off the screen? Does it reappear on the other side or do you have to shoot it again? Can you fire more than 1 dart at a time? or do you have to wait for the one dart to go off the screen before shooting another dart?
Once you have the logic and sequence down,, we can decide the best place to put the code. Everything does not just happen, it all has to be planned out,
If you are having trouble with the language, you need to take a break and learn it some more. You can't build anything without knowing how to use the tools. You will just get frustrated and mad.
You are welcome to look here https://sites.google.com/a/pgcps.org/livecode/
for a simple use of the commands (especially the If statement here https://sites.google.com/a/pgcps.org/li ... ng-choices
You may have a deadline for this code and not think that you have the time but you are not making much progress this way - sending messages/pieces of code and waiting for someone to answer you.
It will get easier and you are doing good for a raw beginner. Just take your time to learn the language and understand what you are doing.
Does that make sense?