You open the Ads.hx from Ads extension folder search for the initialize method and wrap all that code with an if(MyAssets.whirlID!=""). If inside Stencyl->Settings->Mobile the Adbmob Publisher Key is not filled up then the ads will not fire up.
The method should look like this:
public static function initialize(apiCode:String = "none", position:Int = 0):Void
{
if(MyAssets.whirlID!="")
{
#if(mobile && !android && !air)
if(!initialized)
{
set_event_handle(notifyListeners);
initialized = true;
}
#end
#if android
if(!initialized)
{
adwhirlCode = apiCode;
if(_init_func == null)
{
_init_func = JNI.createStaticMethod(ANDROID_CLASS, "initAdmob", "(Ljava/lang/String;I)V", true);
}
var args = new Array<Dynamic>();
args.push(adwhirlCode);
args.push(position);
_init_func(args);
initialized = true;
}
#end
}
}