Minified code has errors in Code - whereas unminified code works perfectly

[RamalingamS]

Actually the post contains 2 questions

1) The following code snippets when part of the files that are minified using Sencha Cmd's
Sencha app Build - produces errors

{
            xtype : 'fieldcontainer',
            combineErrors : true,
            msgTarget : 'qtip',
            fieldLabel : 'Campaign Type',
            allowBlank : false,
            defaults : {
                    hideLabel : true,
                    width : 330
                },
            items : [{
                 xtype : 'radiogroup',
                 id : 'campaignTypeRadioGroup',
                 name : 'campaignType',
                 columns : 2,
                 vertical : true,
                 fieldLabel : 'Campaign Type',
                 layout : 'hbox',
                 items : [{
                     checked : true,
                     boxLabel : 'Ad-Hoc  ',
                     name : 'campaignType',
                     inputValue : 'N'

                 }, {
                     boxLabel : 'Re-curring',
                     inputValue : 'Y',
                     name : 'campaignType'
                 }]
            }]
        },

{
                        xtype : 'fieldcontainer',
                        combineErrors : true,
                        msgTarget : 'qtip',
                        fieldLabel : 'Campaign Type',
                         allowBlank : false,
                        defaults : {
                            hideLabel : true,
                            width : 330
                        },
                        items : [ {
                            xtype : 'radiogroup',
                            id : 'requestcampaignTypeRadioGroup',
                            name : 'campaignTypeInd',
                            vertical : true,
                            layout : 'hbox',
                            items : [{
                                boxLabel : 'Ad-hoc',
                                inputValue : 'N',
                                checked : true,
                                name : 'campaignTypeInd'
                            }, {
                                boxLabel : 'Re-curring',
                                inputValue : 'Y',
                                name : 'campaignTypeInd'
                            }]
                        }]
                }

 {
                                               xtype : 'radiogroup',
                                               width : 500,
                                               id : 'campaignTypeRadioGroupAS',
                                               fieldLabel : 'Campaign Type',
                                               labelSeparator : '',
                                               labelWidth : 130,
                                               labelAlign : 'left',
                                               vertical : true,
                                               margin : '5 5 3 5',
                                               items : [
                                                        {
                                                            boxLabel : 'Ad-Hoc',
                                                            inputValue : 'N',
                                                            name : 'campaignType'
                                                        },
                                                        {
                                                            boxLabel : 'Re-curring',
                                                            inputValue : 'Y',
                                                            name : 'campaignType'
                                                        },
                                                        {
                                                            boxLabel : 'Both',
                                                            name : 'campaignType',
                                                            checked : true,
                                                            ///Need to repalce this with the correct input value
                                                            inputValue : 'B'

                                                        } ]
                                           }

-----------------------
2) Even after removing the above snippets rendering of the viewport fails with the following message

TypeError: 'null' is not an object (evaluating 'u.dom')

Issue appears after the Viewport's initComponent has been Completed

callee is "doInsert" in the class "Ext.dom.Helper"
Called by "append" in the Ext.dom.AbstractHelper
called by "render" in the Ext.util.Renderable
called by the "constructor" in the Ext.AbstractComponent
called by the "callParent" in the "Ext.Base"
called by the "constructor" in the Ext.Component

The arguments passed on the anonymous method called by doInsert is

0: null
1: Object - cls: "x-panel x-panel-default"
id: "ext-comp-1012"
style: Object
tag: "div"
tpl: Object
     $name: "doRenderBody"
     $owner: function j() {return this.constructor.apply(this,arguments)||null;}
     $childEls: Array[1]
     $className: "Ext.layout.container.Container"
     $isClass: true
2: undefined
3: "beforeend"
4: ""
5: true

Any help would be appreciated