I tend to disagree with what is said and/or suggested in several earlier posts.
The reason why BSPlayer partly still shows English texts in spite of the translated version is not mainly, but instead only to a very limited degree, caused by bugs in BSPlayer (e.g. left hand side of Intervideo AC3).
To a much larger extent it is simply caused by the translation being incomplete. The number of "labels" of the translated version should equal the number of labels of the original English version.
E.g. with respect to "Raccourcis & WinLIRC" under "Actions" the "labels" 106 and 107 (Fast forward respectively Fast rewind) are missing in the translated version.
Je regrette que ma réponse n'est pas en français, mais je trouve l'anglais plus facile.
(Pourtant l'anglais est la langue de ce forum)