I didn't read all the comments, so don't know if anyone else suggested this. A few times now, I have successfully got my first few hundred users by offering a

I didn't read all the comments, so don't know if anyone else suggested this. A few times now, I have successfully got my first few hundred users by offering a lifetime discount and positioning it as a limited access beta testing program. Got lots of feedback, and most users kept their accounts for a very long time, even if they weren't using the software, just do they wouldn't lose their discount.