如何使用SugarCRM的Module Builder进行版本控制？

I've created a module using SugarCRM's Module Builder and deployed it. Later, I need to modify (add/remove) fields and relationships from a deployed module. If I make the change in Module Builder and re-deploy the module it will remove all my custom code for the module including the icons I created for the module.I've created a module using SugarCRM's Module B