Full orchestration (in progress) of a march I wrote in 2014 for concert band. Commissioned by the Lake Country Symphonic Band, Mineola, Texas, Mike Holbrook, conductor. Sheet music available (soon) from Lovebird Music, lovebirdmusic.com
Wow! What an honor to be the first to comment. Although it's hard to find words to describe such a beautiful arrangement. You can't stop the video before the end. Watch two or three times for sure. Congratulations on the arrangement.
Use the plugins that NotePerformer installs into Sibelius (Home > Plugins menu). The "Reset Mixer for NotePerformer" plugin sets the channel volume correctly - you can make additional adjustments after than in the Mixer window. Then use the "NotePerformer a2, a3... MIDI message" plugin to set each instrument for the appropriate number of players for that instrument (I like 6 violin 1, 6 violin 2, 4 viola, 4 cello, 4 contrabass). Then set your Reverb (Play > Performance menu) to what sounds best to you (I like "Ambient Hall").