Themeforest theme and WHMCS WP Integration

Alright - I'm considering the purchase of a theme (http://themeforest.net/item/x-the-ultimate-wordpress-theme/5871901) and it looks to be an *extremely* versatile and very highly customizable theme, perhaps the only one I may need for many of my customers.

Prior to the purchase of this, I am not able to get the theme creators to actually "support" the integration of WHMCS into this. They simply say that, "integration of 3rd party plugins is the responsibility of the customer." Understood.

Can you see or find *any* plausible reason that I should NOT be able to use the WHMCS WP Integration plugin that we have with you, into this theme? If you believe that I can, will you (WPMUDev.org) be able to assist in the customization and integration at no additional cost?

You can view MULTIPLE demos of this theme here: http://theme.co/x/#demos

Your expertise in this is very much appreciated.

Thanks in advance,
Matt