After downloadin v6.0.0.0 today and importing my standard content document type, I get the following error:  ".....could not be published because of invalid properties" in the log file.   Which of these properties are invalid in 6 that were valid in 4?  (udt code below).  I should point out that there was no error on importing this udt and creating document types, but when I try to publish, it says invalid properties.  Any help is appreciated.

UDT file content:

<?xml version="1.0" encoding="utf-8"?>
<DocumentType>
  <Info>
    <Name>Master Content</Name>
    <Alias>MasterContent</Alias>
    <Icon>folder.gif</Icon>
    <Thumbnail>folder.png</Thumbnail>
    <Description></Description>
    <AllowedTemplates />
    <DefaultTemplate></DefaultTemplate>
  </Info>
  <Structure />
  <GenericProperties>
    <GenericProperty>
      <Name>Page Title</Name>
      <Alias>pageTitle</Alias>
      <Type>ec15c1e5-9d90-422a-aa52-4f7622c63bea</Type>
      <Definition>0cc0eba1-9960-42c9-bf9b-60e150b429ae</Definition>
      <Tab>Meta</Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Description</Name>
      <Alias>description</Alias>
      <Type>67db8357-ef57-493e-91ac-936d305e0f2a</Type>
      <Definition>c6bac0dd-4ab9-45b1-8e30-e4b619ee5da3</Definition>
      <Tab>Meta</Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Keywords</Name>
      <Alias>keywords</Alias>
      <Type>ec15c1e5-9d90-422a-aa52-4f7622c63bea</Type>
      <Definition>0cc0eba1-9960-42c9-bf9b-60e150b429ae</Definition>
      <Tab>Meta</Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>UmbracoRedirect</Name>
      <Alias>umbracoRedirect</Alias>
      <Type>158aa029-24ed-4948-939e-c3da209e5fba</Type>
      <Definition>a6857c73-d6e9-480c-b6e6-f15f6ad11125</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Umbraco Internal Redirect Id</Name>
      <Alias>umbracoInternalRedirectId</Alias>
      <Type>158aa029-24ed-4948-939e-c3da209e5fba</Type>
      <Definition>a6857c73-d6e9-480c-b6e6-f15f6ad11125</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Umbraco Url Name</Name>
      <Alias>umbracoUrlName</Alias>
      <Type>ec15c1e5-9d90-422a-aa52-4f7622c63bea</Type>
      <Definition>0cc0eba1-9960-42c9-bf9b-60e150b429ae</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Umbraco Url Alias</Name>
      <Alias>umbracoUrlAlias</Alias>
      <Type>ec15c1e5-9d90-422a-aa52-4f7622c63bea</Type>
      <Definition>0cc0eba1-9960-42c9-bf9b-60e150b429ae</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Umbraco Navi Hide</Name>
      <Alias>umbracoNaviHide</Alias>
      <Type>38b352c1-e9f8-4fd8-9324-9a2eab06d97a</Type>
      <Definition>92897bc6-a5f3-4ffe-ae27-f2e7e33dda49</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Section Class</Name>
      <Alias>sectionClasses</Alias>
      <Type>ec15c1e5-9d90-422a-aa52-4f7622c63bea</Type>
      <Definition>0cc0eba1-9960-42c9-bf9b-60e150b429ae</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[Used for CSS styles]]></Description>
    </GenericProperty>
    <GenericProperty>
      <Name>Child Section class</Name>
      <Alias>childSectionClass</Alias>
      <Type>ec15c1e5-9d90-422a-aa52-4f7622c63bea</Type>
      <Definition>0cc0eba1-9960-42c9-bf9b-60e150b429ae</Definition>
      <Tab></Tab>
      <Mandatory>False</Mandatory>
      <Validation></Validation>
      <Description><![CDATA[The css class for all children]]></Description>
    </GenericProperty>
  </GenericProperties>
  <Tabs>
    <Tab>
      <Id>7</Id>
      <Caption>Content</Caption>
    </Tab>
    <Tab>
      <Id>6</Id>
      <Caption>Meta</Caption>
    </Tab>
  </Tabs>
</DocumentType>