The "Roku Smart Home Camera" software on the Roku Express 4K+ is horrible but it doesn't need to be.
The "Smart Home" phone app works just fine (it suffers from some stuttering in HD but it is highly useful). The software on the TV adapter is completely different. Even when the phone app shows all the camera sources, the TV adapter software can't hook up to those same cameras. Unfortunately, the worst connection is always the doorbell video camera, probably the one you want the most. As usual, the program suggests that you reboot and reinstall the cameras; that is stupid as if they all work with the phone app then they are all properly installed and working.
Here are some suggestions to make the "Roku Smart Home Camera" TV adapter software more useful and robust...
Use the same audio/video feed to the adapter as you use for the phone app.
Offer a "view" selection that includes all cameras with live feeds as with a security system.
The recorded video on the subscription service should be accessible on the TV adapter software.
Motion detection should bring up the TV adapter and turn on the HDMI feed (like when you use it manually).
Some options for the picture-in-picture option (such as size, sound, length, time, ect.) could be useful.
These ideas are simple programming concepts that utilize what Roku already has available. A couple of software engineers should be able to make these changes in less than 1 week as most of these subroutines already exist in your software.
Roku has some great products and a great deal of potential... DON'T SCREW IT UP!!!
I have a lot of ideas for utilization of you current software and hardware. Please feel free to contact me at your convenience.