Well, i don't want to sound rude, but even if you are not going to ask for money to support your game you should put way more effort in your game. Don't misunderstand me, but the storyline is very skinny, the leveldesign and lightning also does not look like a lot of work and a high number of polygons is definitly not what you want because it turns your game into a diashow.
So, enough negative comments, here comes the good part:
I recommend you dl Nickydudes official fpsc guide as well as all other guides the forum members like wolf did, as it shows you the possibilities of fpsc and can help you with the technical aspects of fpsc (there also was a leveldesign guide which is absolute win, you might want to look into that). The next step is to browse through the WIP and showcase boards of the forums and read stories and dl every screenie that looks good to you cause you need some sort of inspiration, you cannot create a game out of nothing and this is a good source besides google.
Another thing that might help you is the TGC Game design theory board, which is an absolute win too:
http://forum.thegamecreators.com/?m=forum_read&i=19
PS: i forgot, dynamic bullet penetration is possible with PB variable system and the weapon scipts- simply attach a variable with a unique value for every caliber to the associated weaponscript(preferably a higher value for a stronger bullet) and a script to every entity that only lets bullets pass that exceed the entitys attached value. e.a.: the door let's only pass a weapons bullet that has a (let's call it P-Value) P-value higher than 12, M9 has a P-Value of 9, so nothing happens, Barret has a PV of 13 so it shoots right through it. See? no problem there.
Good luck, Daniel
it's not metal just because it sounds like explosive diarrhea.