Pligg Support

Is there any documentation about pligg?
I have this error in the log:

[10-Apr-2014 00:13:27] PHP Warning: Missing argument 1 for Search::doSearch(), called in *********/libs/sidebarstories.php on line 28 and defined in /home1/darklife/public_html/noticiasvzla/libs/search.php on line 32
Hi, i am new and pligg. Today i install pligg in my site, but in the log show this errors:

[20-Mar-2014 05:26:11] PHP Warning: Table '****_pligg.pligg_files' doesn't exist in /*********/libs/db.php on line 479

How can i fixed?