Hi haytham,
Zoints Local should work just fine next to an installation of vBulletin in another language other than English.... outside of the fact of it being a different language of course

. Just tonight I was looking at a forum completely in Russian (from the banner to the text) but working alongside with a Zoints Local that comes as default in English perfectly. If you have any apprehension about installing though, make sure to backup before you install to play it safe (which should be done before any major modification or hack is applied.)
- Reid