"New game" - Madness Interactive-based

WASD to move, mouse to aim, F to drop your gun, E to switch guns, Q for bullet time, R to reload.

You can buy ammo in the ?Gun Shop? by going to the second menu and clicking Ammunition and choosing the ammo type you want. You need to spawn a gun, pick it up, and see what ammo it uses at the top right of the screen (or you might already have it memorized).

Also, when you have a gun in your hand and you go into the Armory, if you click the Deposit Box and click Deposit Current Gun, then it will appear on the wall behind you.

Hopefully I covered everything.