Did you know this?
“If a BDC model was created by using SharePoint Designer 2010, you must use SharePoint Designer to export the BDC model. If a model that was created by using SharePoint Designer is exported by using Central Administration or the Export-SPBusinessDataCatalogModel cmdlet, the exported model file includes only placeholders for the external content types.”
Now, just to be concise and clear, how is this feature filed? “By Design”!
I hate “bugs by design”!!