First of all the above are only suggestions, see an earlier set of suggestions here,
Solemn feasts doubles of the first class use either Mass II or III.
Doubles of the second class, greater doubles, doubles use any from IV-VIII. Normally Mass IV is used for Apostles, and VIII is used for feasts of the Angels.
The rest you have the right idea.
Feriis IV Temporum (Feria of the IV class)

This is the easy part, the hard part is working out the ordo (calendar) for your place.

Whatever you do, do with real devotion! For example, if you decide to reserve Mass III for First Fridays or Masses of the Sacred Heart, then you are moving toward offering Mass III in honor of the Sacred Heart of Jesus, and you can keep that in mind when singing it.

Feriis IV Temporum are Ember Days - their Latin titles are Feria IV (or Feria VI or Sabbato) Quattuor Temporum, and yes, that would be Mass 18 in the OP/Liber's suggested usage. And yes, Rogation Masses would use Mass 18.

Mass 11, according to the usage above, is for Green Sundays only (and Septuagesimatide Sundays minus the Gloria), not any other Semiduplex day.

No idea what past usage was (or suggested...going to pains to emphasize that the above usage was never mandatory), but presumably, Masses 2 and 3 would be for all Doubles of the 1st Class not of our Lady, while Masses 3 to 8 were for all other Doubles - 2nd Class, major and minor.

Mass 16 is all Green Ferias.

Clear Creek Abbey basically follows this usage, adapted to the modern classification system. Generally (I think there are rare exceptions):

All Solemnities (not of our Lady) would alternate between Masses 2 and 3;
All Feasts would use Mass 4;
All obligatory Memorials usually used Masses 12 and 13, with occasional dipping into Masses 5 to 7;
All optional Memorials alternated Masses 14 and 15;
Green ferias, Mass 16;
Violet ferias/penitential vigils/rogation&Ember Days Mass 18;
Most of Eastertide (including all Sundays and all non Solemnity/Feast saints during the week) Mass 1;
All Green and Septuagesimatide Sundays, Mass 11;
All Violet/Rose Sundays, Mass 17;
All Feasts of our Lady Mass 9, except Saturdays of our Lady used Mass 10.

Literally never use Mass 8...which I think is funny considering that Mass 8 is probably the most well-known in the Church as a whole.

Liber Usualis 1961 p.78 = Liber Brevior #813 1954 p.80
¶ This Ordinary is NOT meant to be a matter of hard and fast rule :
chants from one Mass may be used together with those from others, the
Ferial Masses excepted. In the same way, in order to add greater solemnity,
one or more of the following '' Chants ad libitum " may be employed.

Graduale 1908 p.80 [pasted not proofread]
Qualislibet cantus huius Ordinarii superius in una Missa positus
adhiberi potest etiam in alia, feriis tamen exceptis; itemque
pro qualitate Missae, aut gradu solemnitatis, aliquis potest assumi
ex iis qui subsequuntur.

Hawkins,

IF the question is about pre-55, surely the Post Vatican 2 citation weakens, rather than strengthens, your point?

Does that priest have any reason/source to know that it is law

I've not been given that data, though I gently enquired. I had also quoted the Liber quote presented here. He also said, "Go ahead and do Mass 13 if that's what you have prepared", so "law" seems a little flexible.

Salieri,

The copyright date matters in this case.
Thank you.

Most of the groupings into "Mass II" or "Mass V", etc. are not found in the manuscripts, which generally had all the Kyries, Glorias, etc. grouped together. (In one case, Mass X, the Sanctus was supplied by Dom Pothier in the late 19th century.) The possible exceptions are the chants of Masses I, IX, and XVIII.

So it seems clear that the groupings of Mass ordinaries in the 20th c. Liber have not been around very long. I understand that. And I would be interested to know why they made the groupings that they did given that they were not previously grouped that way.

That being said, it just makes good sense to have a more or less set Mass setting to sing for a given liturgical day, and so I like that we have these ordinaries in the Liber to choose from depending on the day's ranking. I mean as opposed to just picking randomly out of a large number of choices. Obviously there is still an element of choice in the current setup since there is more than one Mass designated for the same liturgical rankings. It was really cool at Clear Creek to become familiar with all 18 Masses (and even some of the Ad Libitum chants) and to associate certain types of days with certain Mass settings.