Developer Alessandro Petrolati did a tutorial on using MIDI NRPN in iVCS3, with the help of his daughter Elena!
NRPN offers a distinct advantage over regular MIDI with 14-bit bit resolution. Regular MIDI is only 7-bit so when you change a knob or fadder you're limited to sending 0-127. This is fine in most cases, but can sound "steppy" in some instances. With 14-bit that number becomes 0-16,383! This is the Holy Grail for buttery smooth filter sweeps. It is also a very rare thing in music tech, but iVCS3 can do it!
iVCS3 with Behringer BCF2000 for 14 bit MIDI NRPN high resolution.