I thought Transitus was either a euphemism for the Feast or a disambiguation from the Sept. 17 Impressionis Sacrorum Stigmatum in Corpore S. Francisci, but one learns something every day. What sort of lineup are you contemplating?
I don't think he's one of those here, but Paul Ellison of San Francisco's Church of the Advent has Englished the Mass Propers, and Palestrina's Hymns are of course on CPDL.
The Franciscans have a Proper Mass with Sequence, Ordinary Mass II or III if double of first class or perhaps IV, or V, VI or VIII if Second class. I would look at the Office Hymns for the extras and the Franciscan books have plenty to choose from.
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