I've been trying device a workflow for upgrading my existing data in a previous version of the LGIM to a newer LGIM schema using X-Ray, just as were explaining. I am running into an issue when I try to create to an updated schema using X-Ray that preserves some changes that I made with the newer version of the LGIM. I had expected when I used the 'Merge Into XML' then import that to a new geodatabase, it would include a combination of missing items from each geodatabase. Instead it seems to have added the fields missing from one source, but not the other. I was expecting the sum of the two.
I also tried to use the Import Using Geoprocessing tool, but it kept giving me an error on the domains. The errors where "Domain Name: Value is required". It appears that I somehow generated some XML with blank domains.
Leon