app/locale/My_Language is right there, but 80% of front-end displays in English.
My_Langage is set up in Back End though.
I guess back end needs more tweaking. Any leads?
1- You need to create a new store view and set the desired translation to this store view.
2- Set Locale Option of Store View.
3- Configure language for CMS pages and static blocks.
Be sure to clear the cache before trying to use your new language.
For more detail, follow these links:
Hope this helps.