So, you are attempting to install the database version. Did you first add the information to the config.inc.php file as mentioned in the readme?
Open the configuration file 'config.inc.php' with a text editor
and set up your database settings.
I haven't installed the database version (using textfile), but I think you also need to set the permissions as shown in the textfile/readme.
Give write permissions to the webserver on the configuration files.
polldata 777 (drwxrwxrwx) (directory)
- 1 666 (-rw-rw-rw)
- 2 666 (-rw-rw-rw)
- 3 666 (-rw-rw-rw)
- session.php 666 (-rw-rw-rw)
templates 777 (drwxrwxrwx) (directory)
| default 777 (drwxrwxrwx) (directory)
- comment.html 666 (-rw-rw-rw)
- display_foot.html 666 (-rw-rw-rw)
- display_head.html 666 (-rw-rw-rw)
- display_loop.html 666 (-rw-rw-rw)
- result_head.html 666 (-rw-rw-rw)
- result_foot.html 666 (-rw-rw-rw)
- result_loop.html 666 (-rw-rw-rw)
| graphic 777 (drwxrwxrwx) (directory)
- ...
include 755 (drwxr-xr-x) (directory)
- config.inc.php 666 (-rw-rw-rw)