Yes, the blank screen feature works very differently in Windows 8/10. In fact, there is no blank screen, it's just the monitor that is turned off. As you probably noticed, the Host offers you to install a special monitor driver which is required if you need to use the blank remote screen feature with Windows 8/10.
As such, the custom text/html/image option will be discontinued starting the very next update. We will remove the related controls from the Viewer interface in the upcoming update.
If screen blanking is turned off, the host user sees the screen as normal. I'm guessing this is a bug in the monitor lock driver for windows 10, but I could be wrong. Is there something I'm doing wrong?
Could you please elaborate on this? If screen blanking is off, the remote user should see the monitor, yes. Or did you mean something different?
Looking forward to your reply.