With Poedit you can edit flp.po that is located in the languages folder of the plugin. Once translated save it into the languages folder and rename both .po and .mo to the translated language appeding flp- to it.
For example if you translated the plugin into spanish, save it as flp-es_ES.mo and flp-es_ES.po and put that files inside the language folder.
Please contribute with the plugin and send us your translation files to include it on next updates.