Thank you for your (very direct) comment on my query… an answer on software would have been more useful since you have much experience. And for my particular project I confirm that I will only use essential oils, absolutes and simple or compounded natural isolates.
Vertofix has a very specific woody/ambery even leather facette… it’s only one of dozens of aroma chemicals that may be used as a base to augment fixation. It is a fixative that will increase staying power but it is far from neutral!