NextGEN plugin is localizable only and delivers adapted .mo files that translate currently the dashboard side.
Beginning by terms of the theme, xili-language « translate » according multilingual rules settings by switching the .mo file. Some framework terms as categories or descriptions are added to this .mo file because currently stable in a cms site.
Your question – Example : Some plugins add a label or button – visible in visitors side but the name of this button or label is inserted in function _e with domain of plugin but not domain of theme… xili-language introduces a tip to capture this term / domain and permits translation…
What happens in NEXTGEN which is like an app in app using his own tables (and not custom posts or custom taxonomies) few not gettext functions are also used …? so it will be very difficult to switch according languages the nextgen images and the descriptions.
The data model is fundamental and xili-language works only on the core of WP and his features with some tips and lot of filters..
Hope that help you !
