Well, WME doesn't support unicode at the moment. It probably will sometime in the future, but only for the string tables. I'm not sure if double-byted characters are required for arabic/hebrew.
Also, WME uses bitmap fonts, not TrueType, i.e. you'd have to create a special bitmap font for those languages. Again, I'm not sure if the standard 256 characters supported would be enough here.
As for alignment, you can now set left/right/center alignment for gui texts and buttons as well as for talk captions, so it shouldn't be a big problem.