Changing default search to custom search

I have installed an app called "collective.gsa64, this app creates a page at /site/search and does what I need it to do.
However the default plone search (which resides on the top right side of the site) uses well, the default search.
How can I change the default search to use this new app for searching?
In digging through the code rabbit hole I have found this template: /zeocluster/eggs/plone.app.layout-2.3.15-py2.7.egg/plone/app/layout/viewlets/searchbox.pt
Should I modify this or is there an easier way to achieve what I want?

Btw, I am using plone 4.3.

Thanks

I've never used this package, but its documentation states that can be enabled via the contol panel configlet:

You can enable or disable the search appliance results view (and operation in general) using the control panel.

Yes, I read the docs. The search appliance is enabled and showing results. However, as stated in my original post I want the default search to use this search functionality instead of whatever plone uses.

Did you disable livesearch?

With or without livesearch makes no difference.
I did change the template to use search instead of @@search so it seems like that fixed it. But now I have a problem that if I enable XDV theme the results page is empty! Any ideas?

It's a long shot; the only repo I could find is at https://github.com/mustap/collective.gsa64 but you might get an answer if you file an issue there. It hasn't been maintained much.