I just tried to register and when i click Register, im still at frontpage.
But no message that confirms that i am registered, you might want to check the template if they have added the code snippet that shows the message on the site.
The code should look like this here:
<jdoc:include type="message" />
first you can add it before this here,to see how the placement of the message looks.
<jdoc:include type="component" />