I know there have been a lot of topics on this in the past but I'm wondering in version 6 how I can go about assigning a document type to a different parent after I've already created it.

I've tried by exporting my document types. Creating a new Master. Editing the exported document types to have this new document type as it's Master. Then importing the document type back in - this works. However, I still have to update my existing content to use this new document type and this is where the problem is. When I update manually in the database and also in the cmsContentXML to refer to the new document type ID my content nodes lose all of their content. I can see it still exists in the database but it's not picking it up.

Is there a procedure I can follow to make this work? I've tried some of the plugins mentioned in other posts with no luck. Or will I just have to redo all the document types with a Master and redo all of the content (this is a possibility as the site doesn't have a huge amount of content at the moment - but for a larger existing site this would be a massive problem)

Thanks,
Ian.