Rotation accuracy in build

I'm having an issue keeping my object rotating in 90 degree increments when I build and run my game. However it seems to work fine in the editor and I know this should be working

Any help would be greatly appreciated. Here's the code i'm currently using

var Player : Transform;
var rotateAmount = 90;
var rotateTime = float;

function Update ()
{
    if ( Input.GetKeyDown("z"))
                           // point,  axis, amount, time
        RotateObject(Player.position,Vector3.forward, 90,1.0);

    if  (Input.GetKeyDown("x"))

        RotateObject(Player.position,Vector3.back, 90,1.0);

    if  (Input.GetKeyDown("c"))

        RotateObject(Player.position,Vector3.left, 90,1.0);

    if  (Input.GetKeyDown("v"))

        RotateObject(Player.position,Vector3.right, 90,1.0);

}

function RotateObject(point : Vector3, axis : Vector3,
                      rotateAmount : float, rotateTime : float) {
    var step : float = 0.0; //non-smoothed
    var rate : float = 1.0/rotateTime; //amount to increase non-smooth step by
    var smoothStep : float = 0.0; //smooth step this time
    var lastStep : float = 0.0; //smooth step last time
    while(step < 1.0) { // until we're done
        step += Time.deltaTime * rate; //increase the step
        smoothStep = Mathf.SmoothStep(0.0, 1.0, step); //get the smooth step
        transform.RotateAround(point, axis, 
                               rotateAmount * (smoothStep - lastStep));
        lastStep = smoothStep; //store the smooth step
        yield;
    }
    //finish any left-over
    if(step > 1.0) transform.RotateAround(point, axis,
                                          rotateAmount * (1.0 - lastStep));
}

"`var rotateTime = float`" is incorrect syntax and won't work. Anyway, it looks like the main issue is that you have nothing to prevent rotating while a rotation is already in progress. Either rewrite the Update function as a coroutine and yield on the RotateObject routine, so input isn't checked while it's running and therefore unwanted rotations are impossible, or have some kind of variable that's set true when rotating and false when not, and don't allow the routine to run if the variable is true.