Hotscam - You might check the network status page under the setup when you're seeing the redundancy error to see exactly where the system thinks it is. From there, you can at least find a particular run of wiring to check out. Beyond that, you might try getting in touch with our tech support directly so they can help you through the issue.
rickw - Because the map changed significantly in 4.0, we did change the zoom levels the various objects show up at under MAP > MAP MENU > MAP ITEMS. I wonder if that's what you're seeing (some things now being decluttered at the zoom level you happened to be looking at). Beyond that, the data that is available now should be the same as it was previously.
Edwardoc - You can't zero it out, and I can't easily check in the next few moments whether that sensor profile changed. I don't think we've changed any of the profiles either (to check this: export your settings; the .sfg file is your sensor file. Download our latest. Crack them both open, compare the relevant entries). If you're using the legacy non-Kavlico mechanical sensors, their physical resistor/wiper mechanisms sometimes get sticky, and this is one of the results. This is one of the few reasons we moved away from those sensors.