Yootheme zoo is a very powerful extension to the joomla CMS. In Zoo everything is arranged from the base component of Elements, and if you need your own element that is not listed with Zoo then you have to create it yourself and example would be adding Google map to it. Yootheme gives a fairly good starting point as to how to create a new Helloworld Document here.
There is a simply way that I started editing code for this is to add code in the display field. Where it is asked to display it in either item view or category view you can inject php code into it to do the things that you want. In this example you can insert the Google map php code into that section thus you can display the google map in either the category view or item view. I am sure there is an easier or neater way to do it, but this is the most straightforward method to get your site working under yootheme zoo and joomla.