Error on upgrading

[Kiran-E-Sehar]

An error has occurred. Please contact vBulletin Support for assistance.

Module: skimlinks, Step 2 Error.

Failed to write css files. Please make sure that the directory 'clientscript/vbulletin_css' is writable.

how to fix please help

thanks in advance

--------------- Added [DATE]1322349228[/DATE] at [TIME]1322349228[/TIME] ---------------

<strong>MySQL Error</strong>   : Unknown column 'phrasegroup_award' in 'field list'<br />
<strong>Error Number</strong>  : 1054<br />
<strong>Request Date</strong>  : Sunday, November 27th 2011 @ 03:32:49 AM<br />
<strong>Error Date</strong>    : Sunday, November 27th 2011 @ 03:33:13 AM<br />
<strong>Script</strong>        : http://www.forum.kiran-e-sehar.com/install/upgrade.php<br />
<strong>Referrer</strong>      : http://www.forum.kiran-e-sehar.com/install/upgrade.php<br />
<strong>Classname</strong>     : vB_Database<br />
<strong>MySQL Version</strong> : 5.0.45-community-nt<br />
</p>]]></error_html>
</errors>

now having this error