Adding analytics code in the header

Our Adwords specialists have suggested manually adding Google Analytics code to the header as the existing Google Analytics addon code does not support cross-domain, sub-domain and re-marketing.

Is the above true? If yes, how do I manually add the code to the header of cs-cart 3.0.4?

Any help will be appreciated.

You may disable GA addon and put your own GA code in index.tpl in

skins/basic/customer/index.tpl id you are using basic template.