I read a solution for this:
Make a Sub-Script without full-privileges-option. Only script-step there is to stop the script again (I don't know the english names). This step gives you the option to pass a result to the main script, which can be "Get(CurrentPrivilegeSetName)".
The other alternative is to pass the privilege set name in the script parameter.
use Get(ScriptParameter) to pull it out.
You can pass multiple parameters separated by line breaks if you want, using GetValue() wrapped around the above.
actually, a third option I just thought of would be to add a global variable to your "On Open" script.
set variable $$priv = Get(CurrentPrivilegeSetName)
then you can reference $$priv in any of your scripts that need to check privilege levels.
you are right. In the end I fixed it by Get(AccountPrivilegeSetName).