If you want to set the transparency of Item when the Light changes, you can do it directly (send Light Value to Item.Opacity) or via the script.
The script would be needed if your light changes from 0 to 100 untill the Opacity changes from 0 to 255.

// items
var Level = IR.GetItem("Main").GetItem("Light Level 1");
var Item = IR.GetItem("Main").GetItem("Light Item 1").GetState(0);
// driver name
var driver = IR.GetDevice("KNX Router (KNXnet/IP)");
//by Start
Item.Opacity = 0;
// change opacity manually (using ScriptCall function)
function OpacityChange ()
{
    Item.Opacity = Level.Value*255/100;
}
// change opacity by Feedback from equipment 
IR.AddListener(IR.EVENT_TAG_CHANGE , driver, function(name,value)
{
   Item.Opacity = Level.Value*255/100;
});

If you want to convert the feedback only use this script:

var FeedbackConvert;
IR.AddListener(IR.EVENT_TAG_CHANGE, IR.GetDevice("KNX"), function(name, value) 
{  
   if (name == "Address 1")
   {
      FeedbackConvert = (value*255)/100
      IR.GetItem("Page 1").GetItem("Item 1").GetState(0).Opacity = FeedbackConvert;
      IR.Log("Value = "+ value)
   }else{
    IR.Log("unknown")
   }
});

Example Project

var Value_Buttons = [0,0]; 

function LoadData(){
   Value_Buttons = IR.GetVariable("Global.Data").split(",");    
   IR.Log(Value_Buttons)
}                

function SaveData(){
   IR.SetVariable("Global.Data", Value_Buttons);    
   IR.Log(Value_Buttons);
}

SaveData();
LoadData();

var Value_Buttons = [[0,0],[1,1]]; 

function LoadData(){
   var data = IR.GetVariable("Global.Data");
   data = data.split(";");
   for(var i = 0; i < data.length; i++)
   Value_Buttons[i] = data[i].split(",");
   IR.Log(Value_Buttons)
}   

function SaveData(){
   var data = "";
   for(var i = 0; i < Value_Buttons.length; i++)
   data += Value_Buttons[i] + ";";
   IR.SetVariable("Global.Data", data);
   IR.Log(data);
}

SaveData();
LoadData();

var Value_Buttons = [[[0,0],[1,1]],[[2,2],[3,3]]]; 

function LoadData(){

   var data_1 = IR.GetVariable("Global.Data");
   var data_2 = [];
   data_1 = data_1.split(":");

   for(var i = 0; i < data_1.length; i++){
      data_2[i] = data_1[i].split(";");
      for(var j = 0; j < data_2[i].length; j++)
         Value_Buttons[i][j] = data_2[i][j].split(",");  
   }
   IR.Log(Value_Buttons);

}                                      

function SaveData()
{
   var data = "";
   for(var i = 0; i < Value_Buttons.length; i++){
      for(var j = 0; j < Value_Buttons[i].length; j++){
         data += Value_Buttons[i][j];         

         if(j < Value_Buttons[i].length -1)
            data += ";"
      }          

      if(i < Value_Buttons.length -1)
         data += ":";
   }

   IR.SetVariable("Global.Data", data);
   IR.Log(data);
}

SaveData(); 
LoadData();
<br/>

Dear everybody,


For fast and convenient adding the Highcross  into your project we created an interface in the Metro style for iPad & iPhone for controlling Highcross.


We would appreciate if you test efficiency of this driver. If you find any bug please let us know.

Download new version

Dear everybody,
We developed the driver to PTN Matrix Switcher. Test it please and write your feedback to us. We attached the database with the driver, and the example project. If you will test it, first of all you must open the GUI and attach the database to your device base. The manual you can find in script.

Dear everybody,
We developed the js driver for Boxee media server. 

Test it please and write your feedback to us. We attached the database with the driver and the demo-project.

Yours,

iRidium Mobile Team

HI! The xComfot driver is available in beta-test now. It can send commands and receive feedback. But the driver may have some bugs: for example, it doesn't request the initial state of a device at its start. All comments to the driver are in Russian, but soon they'll be available in English. We wish you successful testing. 

Dear everybody,


For fast and convenient adding the DuneHD Media Server into your project we created an interface in the Metro style for iPad & iPhone for controlling DuneHD Media Server. 

We would appreciate if you test efficiency of this driver. If you find any bug please let us know.

Download new version

Dear everybody,

For fast and convenient adding the Kramer 2000 / 3000  into your project we created an interface in the Metro style for iPad & iPhone for controlling Kramer 2000 / 3000.

We would appreciate if you test efficiency of this driver. If you find any bug please let us know.

Download new version

Dear everybody,


For fast and convenient adding the  Onkyo into your project we created an interface in the Metro style for iPad & iPhone for controlling  Onkyo.


We would appreciate if you test efficiency of this driver. If you find any bug please let us know

Download new version

Dear everybody,
We developed the js driver for Roku. 
Test it please and write your feedback to us. We attached the database with the driver.


Yours,
iRidium Mobile Team