How to fix Syntax: Unexpected token )

If you are trying to change the position and order of multiple layers based on a changing value for each layer driven by some data or a slider, the workflow in the tutorial is not the workflow I would use.  

The tutorial is too painful to watch, so I am not sure where you apply this expression. The only thing I got out of the tutorial was that the author was making a MOGRT to be used in Premiere Pro.

Tell us where you apply the expression and show us a screenshot by embedding, not uploading using the "Drag & Drop here..." option. Select the layer with the problem code, press the 'u' key twice to reveal all modified properties, take a screenshot, select the screenshot file and copy and paste it to your post, drag it into your post, or use the Toolbar so we can see what you are doing. 

I agree with Mylenium 100%. The expression you shared is incomplete. 

The line 

for (i = 1; <= 4, i++)

makes no sense. I'm also not clear what your sort function is supposed to do. You also have some extraneous spaces in your code, which is critical as it breaks inheritance. The whole code seems incomplete.

Mylenium

The code can be found here!

`pi = 0;
dt = effect("RankTransTime ")("Slider");
sTime = Math.floor(time/dt)*dt;
z = [0,0,0,0];
if (time - sTime < 0.1){
    n = effect("n")("Slider");
    if (Math.floor(n/4) >= pi){
        let r = [];
        for (i = 1; i <= n; i++){
            ssTime = thisComp.layer(i).masterProperty("time").valueAtTime(sTime);
            if (ssTime == 0) ssTime = (n-1)/1000;
            let obj = {t: ssTime, id: i};
            r[i-1] = Object.assign({}, obj);
        }
        r. sort(function(a,b){return b.t - a.t});
        for (i = 1 <= 4, i++){
            z[i-1] = r.findIndex(function(a)return a.id == i + (pi*4)})/20;
}}
z `