I am tagging my Library: use "* ANDNOT mytag:*" search parameter to show untagged resources, select one and start adding mytags.
HOWEVER, as soon as at least one tag is added and Logos updates the Library catalog in the background, the title disappears from view, even though the mytag field is selected and I am still wanting to add more tags.
This is like having a waitress grab your food in the middle of you eating it 
The reason I consider this a BUG is because Logos5 behaves totally different if I select untagged resources by sorting my whole library by tag and opening the "--" (untagged) category. Then the edited resource stays put till I select another resource.