People make mistakes. That’s why anyone worth their salt is using version control systems like Git for their code these days. The closest we can currently come to version control for Drupal products, is use of the revisioning system. And if you’re here, I’ll assume that you know what that is, and what it does.
Open Layers are great, Drupal are great, and the OpenLayers and associated Drupal modules that combine the two are especially great. Unless, like most modern security-conscious websites, you’re using encrypted connections to your server with SSL. In that case, maps are unfortunately invisible wherever they’re used, both on public pages, and in administrative and content editing pages.