Sounds like you're making this more complicated than it is.
The steps are:
1. Open the `zp-config.php.example` file in a text editor.
2. Edit the text in the file and enter the database login credentials for your server (there are instructions once you open it).
3. Save the file.
4. Rename the file to `zp-config.php`
That's it! Then navigate to the setup page, at [http://your-web-site.com]/[zenphoto-install-dir]/zp-core/setup.php
So, you're correct, zp-config.php should not exist yet, until you follow the above procedure to create it. The date or whatever you were looking at means nothing, just follow the steps.
You could have also looked at the `readme.txt` file, or the installation instructions. Those are usually a good place to start, and tell you exactly how to do everything. And, as always with computers, don't be afraid to just experiment and try things.