I havent't seen the slow motion in F.E.A.R but if you want the slow motion to be triggered by a key press (an held, Im not going through toggle) then you will need code that looks like this probably placed in your player action:
if(key_z == 1) //this checks to see if the z key is pressed, any key can be used
{
time_factor = 0.2;
}
else
{
if(key_z == 0)
{
time_factor = 1;
}
}
For this you will have to put *time after all your speed changes. By this I mean
ent_move(vector(my.speed_x*time,0,0),nullvector)
the *time ensures that all speeds are changed by time.
Sydan