Click [Select Qualifier], check qualifiers in the dialog as needed and click [Save] button.
Then, you can find input fields for qualifiers on 7.Annotation.

Related to this issue, in case of selecting “other” on 6. template, you have to specify some features other than source. So, click [Add feature] and select some feature on the list.

Reference
7.Annotation (when “other” was selected at template)