Fatal error

I had the same problem. I read some blogs, they suggested a solution and it worked for me! thought may be useful for you, too:
1) download the .zip file of the plugin.
2) Extract it.
3) Go to the file where the Fatal Error says. In my case it was: page-navi-slider\inc\settings.php
4) Open the file using a php editor program (I use Notepad++).
5) Go to the line mentioned in the error. Mine was 165
6) The line should contain a function which has ‘&’ that matches in the call to function.
7) Delete the ‘&’. In my case I deleted three ‘&’s from three consecutive lines.
8) It is activated!

Thanks for your comments.
I can see in PHP documentation that ... And as of PHP 5.4.0, call-time pass-by-reference was removed, so using it will raise a fatal error.

I will release a new version in the coming days to fix that bug.

Excellent. Thanks for the quick response.

The version 1.2.1 is on line.
The bug should be fixed (it works fine on my test environment).