I've moved your post to the 360 forum. The error code you mentioned (CS2400) doesn't apply to V6 or tivo boxes, but only to 360 and Stream boxes.
Error CS2400 mainly affects BBC channels - there is a workaround. You can force the BBC channel to play without the pop up reappearing if you hit the back button on the 360 remote when the error message appears, and then press pause and play. Basically it ties in with a loss of internet connection and the BBC channels trying to connect to the red button even if you haven't pressed it. It can also signify the beggings of a hard drive error.
It sounds like you migrated from a V6 to 360 TV system. That migration process deletes the tivo operating system from the box when the hard drive is formatted and replaces it with Liberty Global's (VM's owners) in house Horizon Entertainement system.
So the box is now termed a 360 box s it has no remnants remaining from the tivo/V6 system.
The errors you describe (channel and app icons not showing, apps not loading) are a result of a loss of internet connection. Since you are connected by ethernet cable this shouldn't be a problem.
It's possible that your ethernet cable is faulty, or that the ethernet port on the 360 box or VM hub is faulty. Which VM hub do you have? Have you tried a different ethernet cable? Or a different ethernet port on your hub?
When you tried setting up a wifi connection to the 360 box then providing you removed the ethernet cable form the 360 box and entered the Wifi SSID and password it should have worked.
The streaming apps being signed out can be due to loss of internet connection, but can also be caused by turning off the 360 box at either the wall plug, or the rocker switch on the back of the 360 box. This can also be the sign of a hard drive issue , which might also be linked to the orange light showing as that can be another indcator of a possible due to hard drive issue.
Does your 360 box lose recordings?
What happens if you pause a live TV program for a few of minutes and then play it back again?
Have you tried a factory reset?
To factory reset go to Settings (the cog at the end of the Home menu) > System > Factory Reset. It's actually misnamed and only a partial system reset and not a complete factory reset. You are given 2 options
Keep Recordings
Format Disk
Select Keep Recordings, which means you won't lose your recordings, and any planned recordings, or series links you've set up. You may have to sign into your apps such as iPlayer, Prime, Netflix and ITVX again.