My kids go/went to a school with an almost identical grading system. As far as I know there is nowhere to see a distribution of grades for the entire class (so no ranking). My kid applied to 6 BS last year and not one asked for any clarification on the grading or school report.
The school is definitely not a known entity to BS admission departments either, since boarding school in my neck of the woods is seen as something you send your kid to if they need behavioral intervention!