It's true you can not use VST's. Why not try Sonar? It's quite a hefty price unfortunately -- I don't uave the website or anything offhand, but a Google search might help you with that. ALso, Cubase isn't one bit accessible from my tryings with it, --- JAWS would not read any element of any part of the screen except random graphic numbers. Then again my display chain was having extreme issues. I'm open to try it again but as I don't own a "real" keyboard, I've used the QWS onscreen keyboard. Which is ok for the most part, but I got to warn some of you, it's quite laggy. Which is why I set out to find Roland's incredibly old Virtual Sound Canvas and Yamaha Sy-XG50 soft synthesizers which worked better.
Sorry for the unorganized nature of this post but I just thought of a way to access VST's with QWS. On the site I posted above there should be an article link, with another link called using VSt's with QWS or something. So first click on Articles then on VST's, it's probably better to use the find function of your screen access software because I don't have the quote offhand. Plus it's quicker in my experience to just tap a button and type in VST.
HTH somewhat.
Once again sorry for the somewhat unorganized nature of this post as I glop back and forth from one idea to the next...