NumberGuidesGrid.js

 var doc = app.activeDocument;
 var guides = app.activeDocument.guides;
 var w = doc.width;
 var h = doc.height;

 function MakeGuidesGrid(numVerticalGuides, gutterVertical, numHorisontalGuides, gutterHorisontal) {
     if (numHorisontalGuides !== 0) {
         var j = h / numHorisontalGuides;
         for (var i = 0; i < numHorisontalGuides; i++) {
             guides.add(Direction.HORIZONTAL, j * i);
             guides.add(Direction.HORIZONTAL, j * i + gutterHorisontal);
         }
     }
     if (numVerticalGuides !== 0) {
         var z = w / numVerticalGuides;
         for (var i = 0; i < numVerticalGuides; i++) {
             guides.add(Direction.VERTICAL, z * i);
             guides.add(Direction.VERTICAL, z * i + gutterVertical);
         }
     }
 }
 MakeGuidesGrid(parseInt(prompt("Insert the number of Vertical guides", 40)), parseInt(prompt("Insert the Vertical gutter size", 10)), parseInt(prompt("Insert the number of Horisontal guides", 40)), parseInt(prompt("Insert the Vertical gutter size", 10)));
 //MakeGuidesGrid(40,10,40,10)