Hi @Franck_R,
I can see why that would be a problem! First, something I can help with: the following jsl returns the current system/jmp language locale:
System Service( Get Language Code );
For instance, if running on a computer set to an English display language, this will return "en."
With that information, you can at least identify when you need your script to make a change before running. But, this is where it might be tricky. Are your scripts running on a Mac or Windows machine? On Windows machines, language preferences are set in the jmp preferences and *should* be able to be changed via script. On Mac, language preferences are set in the MacOS preferences, and I expect it will be a bit more tricky to set via jsl (but not impossible given that we can use RunProgram() in jsl).
That said, on the "easier" problem, Windows machines, I haven't been successful in finding the right jsl to set the jmp language. There is the additional wrinkle that after changing the jmp language it's often best to restart jmp because certain displays will not update to the selected language until jmp is quit and reopened. That presents a bit of a problem if you want to have your scripts to work as you described: make the language change, evaluate, and then return to the initial language settings.
I'll keep trying some things, and hopefully others have some additional suggestions.
@julian