AngularJS 1.2.0rc1 directive problem

HTML

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0/angular.min.js"></script>
<div ng-controller="basicController">
<form name="form">
    <div ng-repeat="f in fields">
        <div data-render data-model="f"></div>
    </div>
    <button ng-disabled="form.$invalid">submit</button>
</form>
</div>

JavaScript

// inner form validations
var app = angular.module('app', []);

// Directives
// ----------
function basicController($scope){
    $scope.fields = [{
        name: 'MyNumber',
        value: null,
        type: 'number'
    },{
        name: 'myText',
        value: null,
        type: 'text'
    }];
};

app.directive('render', function($compile){
    return {
        scope: {model: '='},
        restrict: 'A',
        replace: true,
        template:
      '<div class="product-option-selector">'+
      '</div>',
    link: function(scope, element){
      var directive = null;
        
        switch(scope.model.type){
        case 'number':
          directive =
              '<div data-item-number data-model="model"></div>';
          break;
        case 'text':
          var directive =
              '<div data-item data-model="model"></div>';
          break;
        case 'radio':
          var directive =
              '<div fg-product-option-selector-radio option="option" item="item" index="index"></div>';
          break;
      }
      if(!directive) return;
      
      directive = '<div>'+directive+'</div>';
      // Do Not compile the element NOT beeing part of the DOM
      //$(element).append($compile(directive)(scope));
      
      // Firstly include in the DOM, then compile
      var result = $(directive).appendTo(element);
      $compile(result)(scope);
    }
    }
});

app.directive('item', function(){
    return {
        scope: {model: '='},
        restrict: 'A',
        replace: true,
        template: 
            '<ng-form name="innerForm">'+
            '{{model.name}}'+
             '<input type="text" name="innerVal" ng-model="model.value" required></input>'+
        '</ng-form>'
    }
});

app.directive('itemNumber', function(){
    return {
        scope: {model: '='},
        restrict: 'A',
        replace: true,
        template: 
            '<ng-form name="innerForm">'+
            '{{model.name}}'+
             '<input type="number"...