I have a similar problem. I am calling a module in which I want to use center and zoom. I do not want to use extent because that would require 4 entries of non human-relatable location points plus the zoom factor per location. I have tried the documentation for center and zoom but I cannot find the right formula (code) to use in the called module via require. I have tried passing the map object as a variable to the module and even though the map object is declared globally, it is not recognized in the module. What do I need to do to get center and zoom to function appropriately?
If you pass the map object to your module as a parameter in the constructor you should be able to access that map's properties and methods. Almost all of the widgets in the API have the map object passed to them in this manner. Do you have a code sample available that I can test?