also I had a look at the sauce

and i want to know how to change wasd to the arrow keys for movement (being left handed and all)
look in game_init script and change this
ini_open("Setting.data");
global.left = ini_read_real("Controls","Left",ord('A'));
global.right = ini_read_real("Controls","Right",ord('D'));
global.up = ini_read_real("Controls","Up",ord('W'));
global.down = ini_read_real("Controls","Down",ord('S'));
//global.leftmouse = ini_read_real("Controls","LeftMouse",mb_left);
//global.rightmouse = ini_read_real("Controls","RightMouse",mb_right);
//global.middlemouse = ini_read_real("Controls","MiddleMouse",mb_middle);
global.switchgun = ini_read_real("Controls","Switch",ord('Q'));
global.use = ini_read_real("Controls","Use",ord('E'));
global.volume=ini_read_real("Options","Volume",1);
global.musicvolume=ini_read_real("Options","Music",1);
ini_close();
to this
ini_open("Setting.data");
global.left = ini_read_real("Controls","Left",vk_left);
global.right = ini_read_real("Controls","Right",vk_right);
global.up = ini_read_real("Controls","Up",vk_up);
global.down = ini_read_real("Controls","Down",vk_down);
//global.leftmouse = ini_read_real("Controls","LeftMouse",mb_left);
//global.rightmouse = ini_read_real("Controls","RightMouse",mb_right);
//global.middlemouse = ini_read_real("Controls","MiddleMouse",mb_middle);
global.switchgun = ini_read_real("Controls","Switch",ord('Q'));
global.use = ini_read_real("Controls","Use",ord('E'));
global.volume=ini_read_real("Options","Volume",1);
global.musicvolume=ini_read_real("Options","Music",1);
ini_close();
i going to add the change key feature but got no time so...
also,the"no infected" bug had been fixed
more keyboard button:
EDIT:to fix that problem,play in harder difficulty.that call the"No Infected" bug