How exactly does one get this plugin to work?

I’m sure I’m missing something, but I can’t tell what from all I have read in the documentation.

The plugin is installed and activated.

I’m trying to run a script which is included in a page by way of the [include.me] plugin and short code. The script sets a $_SESSION[‘var’] and contains a link to another page. When I follow the link, the $_SESSION[‘var’] doesn’t seem to exist. So the session doesn’t seem to exist.

https://agility.events/admin-test/ … if it were to work correctly, the on-screen display would change and the link would not appear to see if it carries over.

In an attempt to determine whether this was a problem due to no session_start(), I tried to add that to the code and got this:

Warning: ini_set(): A session is active. You cannot change the session module’s ini settings at this time in /home/agilityevents/public_html/wp-content/plugins/wp-native-php-sessions/pantheon-sessions.php on line 115

Warning: Cannot modify header information – headers already sent by (output started at /home/agilityevents/public_html/wp-content/plugins/wp-native-php-sessions/pantheon-sessions.php:115) in /home/agilityevents/public_html/wp-includes/pluggable.php on line 1179

So it looks like your plugin handles establishing the session. Great! Still – I can’t store anything in the $_SESSION array.

Any thoughts on what to do at this point? Your guidance would be GREATLY appreciated!