Andi,
I feel like an idiot for not having discovered the Sibelius presets earlier. Now that I am using VE Pro and VI Pro, and loading the Sibelius presets, the results are far superior to what I was getting loading from the Matrix files. Thanks for going to all the trouble to setup these presets so beautifully.
There was a timbral change in the solo voices that was driving me crazy until I realized that slurs (to indicate several notes with the same text) triggered it. So now I could use the Sibelius inspector to turn the playback of a slur in solo voices, and that has solved that problem.
Happy camper,
Randall