There is a couple of ways to do it, but not via command line parameters:
1. Direct reading/writing of the database. We use a standard SQLite 3 database that can be read and written from many programming languages and environments. You can find it via the path shown under the Storage tab in menu File - Settings.
Grab any SQLite management tool like SQLiteSpy and you can read this database. Rules are stored in the RULE table and you will need to restart the service after any changes.
2. There is an XML-based protocol and you can use cURL to send data to the service. Below is an input example and a rule template attached. For a custom rule, you can create a rule you need, copy it to the clipboard and paste into a text editor. Then take the contents between the <root> tags and insert it between the <item> tags, as it was done in the example.
cURL console input:
curl -X POST --header "Content-Type:text/xml;charset=UTF-8" --data-binary @file.xml admin@localhost:8701