I wish I knew how to help you, but I don't really know that much myself. Hopefully someone else can respond to your question. I figured it would be better to respond with this, rather than let you feel you were ignored.
God bless you for your efforts. May he enlighten us all to help us learn.
As for this forum, I only fill happines
I found here many neumes and rare chants, I was looking many years
Also found friends to learn more about byz. style
As for this topic
I believe most members here have nice understanding of scales
So they don't need any virtual instrument
But I am beginner to scales, and it is interesting playng and learning scales on PC
But I believe easy way is to start with FL studio (DAW)
Load sytrus (channels/add one/sytrus
Than drag and drop over sytrus this pressets (in attach)
And play with your PC Keyboard, or Midi Keyb. if you have one
D, E, F, G, A, B, C, D
C, D, E, F, G, A, B, C
D, Eb, F#, G, A, Bb, C#, D
I don't know how many people would read my reply to this question since it was posted last year...
After spending a lot of time in the app store I found an instrument that has the scales and the the Byzantine tones with their proper Greek names. It is called:
"World Scales" (for iPad) I am pretty excited about it. For less than $5 I have a good isokratima and the unbelievable aspect of it is that it has in the instruments list the option "Byzantine choir" that has human voices recorded. It sounds really good. A small amplifier turns your iPad in a real Ison machine and you'll have a bunch of people to hold the ison for you.
I hope this helps. It would be interesting too see some other opinions on this.