This is a simple ufo mode but is really cool for making cinematic on Plutonium, is nothing to hard to make or to hard to use.
To implement the code on your GSC mods just add player thread enable_ufo_mod() in onPlayerConnect().

Like:

onPlayerConnect()
{
    for(;;)
    {
        level waittill("connected", player);
        player thread onPlayerSpawned();
        player thread enable_ufo_mod();
    }
}

vector_scal(vec, scale){
    vec = (vec[0] * scale, vec[1] * scale, vec[2] * scale);
    return vec;
}
doUFOMode(){
    self endon("EndUFOMode");
    self.Fly = 0;
    UFO = spawn("script_model",self.origin);
    for(;;){
        if(self FragButtonPressed()){
       	 	self setclientuivisibilityflag( "hud_visible", 0 );
        	self disableweapons();
            self playerLinkTo(UFO);
            self.Fly = 1;
        }else{
        	self setclientuivisibilityflag( "hud_visible", 1 );
            self unlink();
            self enableweapons();
            self.Fly = 0;
        }
        if(self.Fly == 1){
            Fly = self.origin+vector_scal(anglesToForward(self getPlayerAngles()),
            											  20 // Change this vaule to move slower and faster, this is how dustance far you go when you move
            											  );
            UFO moveTo(Fly,
            		   .1 // Change this vaule to move slower and faster, thi is the wait time to go from A pos To B pos
            );
        }
        wait .001;
    }

}
enable_ufo_mod(){
	ufo_state = false;
	for(;;){
		if(self actionslotonebuttonpressed() && self adsbuttonpressed() && !ufo_state){
			self iprintln("UFO Mode ^2ON");
			ufo_state = true;
			self thread doUFOMode();
		}else if(ufo_state && self actionslotonebuttonpressed() && self adsbuttonpressed()){
			self iprintln("UFO Mode ^1OFF");
			ufo_state = false;
			self notify("EndUFOMode");
		}
		wait .001;
	}

}

To go out of the map without dyng on Zombies just add level.player_out_of_playable_area_monitor = 0; inside your init

Like:

init(){
       level.player_out_of_playable_area_monitor = 0;
}

To turn on and off ufo mod just press:

• Action slot 1 button
• Aim/Scope button