The ini *should* be created by the script itself, and *should* have accumulated some data in the meantime as well.
It's located at a subdirectory of your mIRCS "main" directory (the place where mirc is storing basic settings in e.g. the mirc.ini).
To see the exact location the script is pointing to, type (or paste) in a window:
//echo -a $mircdirini\ips.ini
The script itself is refering to:
//echo -a $qt($shortfn($mircdirini\ips.ini))
...which is technically the same, just a "short filename" version of that location with quotation marks arround it, to play safe (as there may be spaces in a file path that else can cause errors in connection with certain script commands etc).
Do you find the ips.ini there?
If yes, is it empty?
If it's not empty - please remove it, the script will create it again.
I can hardly think of a reason why the script should not write to it, maybe someone else reading this post has...
The text event which performs the /writeini is working as well,'cause you confirmed yesterday that the "extra" line produced messages at #admins.