oStorybook 5.05.06 on Linux Mint
1) Create a Tag, create a Tag Link, nothing shows on the Tag Links page. I can tell it was created, because deleting the tag warns that the link will also be deleted.
2) There's an Attributes column available on the Character list, and an Attributes table, but I can't find how to link an Attribute to a Character. I used Attributes fairly heavily in a couple documents in old versions, so I kind of miss that. And without it, I can't think of a good use for the column on the screen or for the table.
3) Scenes have an "Informative" field. This does not say what the field is for or what it does, and the old documentation doesn't mention it. I've figured out that what it does is exclude the scene from book/reading view, exports, and the like. (Which I have previously done by having the scene not be part of a chapter.) I suggest changing the label on that column to "Exclude" which also has the advantage of taking less room on the field-name line. Oh, and making it appear as a checkbox instead of a text field.