I'm sure they appreciate your feedback. They seem to be responsive, although they may not be able to get everything resolved in a timely manner.
To get to the on screen keyboard on Win7, you have to click on the Ease of Access button on the bottom left corner of the login screen. Then open up the on-screen keyboard (#4 I think). There, you can run the CAD command.
Yes, it's abit buggy, but I'm sure they know that they won't get much paying subscribers until the bugs are worked out. They just need us to be patient and continue to offer feedback...