When adding a double-star object (e.g. hj1000) by clicking the [+] button at bottom left, the only possibility is to add empty object. Adding an empty object, then looking up the object you were looking for in the first place does work.

This is because double star observer IDs are not "true" IDs.

Fixed. If any of the WDS catalogues are present, and the ID is a valid double star observer ID, then those WDS catalogues will be searched.