As far as language goes, here is what the
Constitution on the Sacred Liturgy has to say:36. 1. Particular law remaining in force, the use of the Latin language is to be preserved in the Latin rites.
2. But since the use of the mother tongue, whether in the Mass, the administration of the sacraments, or other parts of the liturgy, frequently may be of great advantage to the people, the limits of its employment may be extended. This will apply in the first place to the readings and directives, and to some of the prayers and chants, according to the regulations on this matter to be laid down separately in subsequent chapters.
3. These norms being observed, it is for the competent territorial ecclesiastical authority mentioned in Art. 22, 2, to decide whether, and to what extent, the vernacular language is to be used; their decrees are to be approved, that is, confirmed, by the Apostolic See. And, whenever it seems to be called for, this authority is to consult with bishops of neighboring regions which have the same language.
4. Translations from the Latin text into the mother tongue intended for use in the liturgy must be approved by the competent territorial ecclesiastical authority mentioned above.
54. In Masses which are celebrated with the people, a suitable place may be allotted to their mother tongue. This is to apply in the first place to the readings and “the common prayer,” but also, as local conditions may warrant, to those parts which pertain to the people, according to the norm laid down in Art. 36 of this Constitution.**Nevertheless steps should be taken so that the faithful may also be able to say or to sing together in Latin those parts of the Ordinary of the Mass which pertain to them. **
And wherever a more extended use of the mother tongue within the Mass appears desirable, the regulation laid down in Art. 40 of this Constitution is to be observed.
As for facing the people, I have a copy of the 1974 Sacramentary, and this is what it says in the rubrics at the start of the Communion Rite:
The priest genuflects. Taking the host, he raises it slightly over the paten and, facing the people, says aloud:
This is the Lamb of God who takes away the sins of the world…
It hardly seems likely that there would be a need to specify that the priest faced the people at that point if it was presumed that he was facing them from the beginning. It was allowed but I don’t think Rome ever envisaged that it would become the norm.
