Openscore: Should I use separate instruments, when for the same "instrument" the instrument names in individual parts differs (choir and instruments)?

Concerning, that a score must contain all of the instruments from all of the movements (so that's possible to join the movements later):

In the mass in b minor there's in different parts a different order of the choir singers, for example: "Soprano I", "Soprano II", "Alto", "Tenore", "Basso"

in another part: "Soprano I,II", "Alto", "Tenore", "Basso"

in another: "Soprano I", "Alto I", "Tenore I", "Basso I", "Soprano II", "Alto II", "Tenore II", "Basso II"

in the final piece: "Soprano", "Alto", "Tenore", "Basso"

Does it mean I've to add for different "instrument names" of the same chorus part/voice a separate instrument (for example "Soprano I,II", "Soprano I" and "Soprano" should be notated in three different instruments), so that the result after joining looks correct?

A similar question to "Oboe d'amore" in one parts and "Oboe" in other (never in the same):

Oboe d'amore is written in the original score in concert pitch (without transposition), so in the same key signature as Oboe. I suppose despite of this I've to use two seperate instruments?

And last: Similar to "Soprano I,II": there are sometimes for "Flauto traverso" two staffs "Flauto traverso I", "Flauto traverso II" (when they are playing different notes and) sometimes "Flauto traverso I,II" (when they are playing the same notes). Is the last one a separate instrument or how should I indicate this?