Ok, I tried to upgrade firmware on my 5232 4k to the 20170418 firmware using the upgrade control in the nvr setup. I wanted to see if it would correct my skipped frames problem. However, after reboot the nvr is not accessible using the configtool, but is accessible using the IP address of the nvr directly. The nvr doesn't see any cameras, and trying to use the nvr upgrade to return to the 20160721 firmware doesn't work because it doesn't seem to recognize the .bin file. Some settings were retained, since my password is recognized, and I can access the nvr menu. But the nvr can't see recordings, cameras, etc. What's my best course of action at this point?