I made some changes to the template and got this plugin to work for me.
in the styles and themes, select style manager and goto your current theme and select edit templates.
Find the template vbsocialregistration template and click on it to open.
scroll down to the bottom and change "Test" to Join xxx site today!".
change the ./register.php to register.php
you can see the text that needs change here in red.
Code:
<vb:if condition="$bbuserinfo['userid'] == 0">
<section id="vbsocialregcallout" class="container clone_1 section-vbsocialregcallout fix">
<div class="texture"><div class="content"><div class="content-pad">
<div class="vbsocialregcallout-area media fix with-callsub">
<div class="vbsocialregcallout_action img rtimg">
<a class="vbsocialreg vbsocialreg-important vbsocialregbuttonbig" href="register.php
"STYLE="TEXT-DECORATION: NONE">{vb:raw vboptions.registerbutton}</a> </div>
<div class="vbsocialregcallout_text bd">
<div class="vbsocialregcallout_text-pad">
<h2 class="vbsocialregcallout_head noimage" style="margin-top: 2px; font-size:28px; margin-left:5px; color:#000;">Join xxxx site Today!</h2><p class="vbsocialregcallout_sub subhead noimage" style="margin-top:-3px;margin-left:50px; color:#000; font-size: 20px;">"Its' free and it takes less than 1 minute!"</p> </div>
</div>
</div>
</div></div></div></section>
</vb:if>