First I think that people seem to be being a bit harsh considering some of the crap that populates this site. Second, it did have some issues. What I noticed were the following:
1. Some of the arrows didn't work. In a way that is okay because they obviously don't lead to the end. But they shouldn't be there if they don't work. I know it is a pain but you should go back through your entire maze and bugcheck the arrows even to places in the maze that don't lead out.
2. Logic is not something you should look to most escape games for. That being said I won the game much too quickly to notice any flaws to your 3d logic. However the game did not feel 3d to me. Three way non tangential intersections (Y intersections) are probably a bad choice. Some of the tunnles and stairwells also seemed to be at odd angles and did detract from the game.
3. Graphics. The graphics aren't so hot, some things you could do to improve this are:
a. Texture your walls, and floor. For this game brick or cinderblock would probably look nice.
b. Add a ceiling so you get the feeling you are looking down a tunnel. Keep your light sources on the ceiling or walls. Either dangling bare bulbs or torches would look nice. Remember when picking the light source to think about how difficult it will be to make it look like the light is comming from there. If you don't want motion lightbulbs are probably the way to go.
c. Variety in the graphics. Maybe while you are drawing out your maze (there are maze generators online for free by the by that will make 2D mazes that you can overlay levels to make 3d mazes) you can create zones, or maybe vary the look by the depth of the dungeon you are on.
d. Your arrows could use some finess, you should try making them look like they are either part of the scene(wall signs). Or like they are hovering there. The ones you have now, just don't look right.
e. Try either making or finding a picture that is a bit more ominous for the ending. Your end picture makes me think 'yay camping'.
4. The music seems to be set to start (again) when either the final screen shows, when you click the final arrow, or when the button pops up to restart the game. If you run back through your code you should find something on one of those events that triggers it. It might not be a direct trigger either it could do with how you coded something that is not quite obvious.
5. As it was said before it is very, very short. In addition to the other misgivings this is a huge problem. I was still trying to get my bearings in the game when suddenly I was out. As I had said before there are free maze generators online. Some of these can create very large mazes. You can actually take these and overlay them to quickly create the layout for a several leveled, and proportional maze. Keep in mind as you draw this out how much area you cover each time you move. This will keep the 'feel' of the maze real.
6. Perhaps some ambient sounds rather than music would be more suited to the game.
I think that a 3D maze is a good idea, but this really needs some work. I hope you take what I have said and actually put it to use, I know it takes time, but taking a long time to put out something good is much better than getting frustrated and putting out something less than the best you can do. Also IMHO it is not cool to threaten to remove peoples reviews, in fact you might find you get more helpful reviews without starting things off on a combative foot. Just my oppinion.