How can I export my translation changes? I am using Core Module Locale in Drupal 7. What is the easiest way to export just my language changes? How do I find out which strings have been modified?
With locale module, you have an export tab here : admin/config/regional/translate/export. Or through the menu : Configuration > Regional and language > Export.

On a fresh installation, active the locale module and go to the import tab : admin/config/regional/translate/import. Or through the menu : Configuration > Regional and language > Import.