Archetypes like openEHR-EHR-OBSERVATION.blood_pressure.v1 with four translations are huge and tedious to process the languages.
openEHR should adopt the standard use internationalization (i18n) and localization (i10n) tools that use gettext catalogs. This is the industry standard approach to performing translations. Tools like POEdit are open source and cross platform http://www.poedit.net/
More info about gettext is here: http://www.gnu.org/software/gettext/manual/gettext.html though it is about the GNU set of tools there are others.
What will openEHR-EHR-OBSERVATION.blood_pressure.v1 look like with 10, 15, 100 translations?