Each entry has an tag/question as label which is shown to the user while labeling, and an export key which is used to export labels. You are free to choose the label, but export keys have a few restrictions.
The key restrictions are:
lower case only
between 1 and 30 characters
may include 0 - 9, _, ., -
can't be one of <<link to forbidden keywords>>
tags, questions and export keys must be unique per label-configuration.
Deleting an entry
You may delete an entry by clicking on the delete icon on it. This will also delete all nested entries! You can also delete all entries at once by clicking on the "Delete config" button.