464 Keyboard and SCART Issues

[Nomad]

Hey all,

I dismantled my 464 to give it a well deserved clean but when I reassembled it, turned on the TV and the computer, there was no display. The computer's LED shone at the full power and the DDI-5 responded to button presses so I connected the 464 to another TV via SCART and experienced the same issue - no display.
Google is my friend so I had a look to see if this is a known problem and I found YouTube videos and threads on here involving no video signals and/or dead machines. I've still got the CTM-644 that came with the 464 and working through a process of elimination, I set them up. Success! It displayed the video image from the 464 perfectly.

Am I correct in assuming that basically my SCART cable has given up the ghost?
Also, I noticed that every single key works with the exception of DEL. I've tried ensuring the both cables from the keyboard are firmly connected to the motherboard but it doesn't seem to have made a difference. Is there any way that I can correct this? I assumed that perhaps the membrane had developed a fault but then wouldn't other keys have been affected?

I'd appreciate your insights and suggestions.