[Cap'n Steve]

Did you modify the templates? Here's what the quote_rating1 template should look like:

$vbphrase[rate_this_quote]: 
<form name="quote$quote[quoteid]">
<input type="button" name="plus" id="plus" value="+" class="vote" onclick="rateQuote(\'plus\', $quote[quoteid], \'quote$quote[quoteid]\');" />
&nbsp;
<input type="button" name="minus" id="minus" value="-" class="vote" onclick="rateQuote(\'minus\', $quote[quoteid], \'quote$quote[quoteid]\');" />
</form>

Notice that it actually uses a javascript function to fill in a hidden form, which is submitted all at once by the vote button at the bottom of the page.

EDIT: I just noticed rating your random quote doesn't work either. It might have something to do the javascript, although the rating does actually get recorded, for some reason it's not redirecting you back to the forum home page. The only thing I can think of is that there's something wrong with your $vboptions['forumhome'] variable, because that's what it redirects to.