Unlocking "add" button for new country in editor

[Sangue Blu]

Hello, I was trying to unlock adding countries option in editor and I was looking in XML files. I found "hide" value for buttons "add" and "delete", also unlocked duplicate option but they won't works. "Add" button is just dead, "duplicate" is switching me to Jugoslavia edit view, number of records is the same, editor counts this all as errors in specifics of file.
I'm sure there is a way to unlock this, I was looking for pattern beetwen few XML's where we are able to add new records like clubs, cities, players but I didn't found anything. Can someone look at these xml's?

Here is the path
C:\Program Files (x86)\Steam\steamapps\common\Football Manager 2017 Editor\data\format
and the lines for unlocking buttons I found in (..)database\nation.xml

<!-- Continent -->
<record>
<flags id="field" value="Ncti"/>
<string id="name" value="Continent"/>
<flags id="type" value="database_record_unique_id"/>
<flags id="database_table_type" value="continent"/>
<boolean id="is_client_field" value="true"/>
<boolean id="is_read_only" value="true"/>

change both "true" values to "false"

View attachment 116352