All fixed, 2 Hotpoint tabs (one each side near the front of the machine) are prised out with a screwdriver exposing two recessed fixing screws. Take screws out, push and lift the machine top to remove. You are now able to see inside the machine and, if you are a repair mechanic (which the person who did this was) you'll recognise that if you push down on the central drum and there's very little resistance it's because the shock absorbers have gone. What you do then, if you're not a mechanic with the spare parts to hand, is down to you - replacing the things requires getting into the underside of the machine. Having got no reply here I booked an engineer from Whirlpool (Hotpoint Service to us hoi-polloi) - haggle the price they quote, it works! - who turned up, did all of the above, put the machine back together, tested it and left. You're welcome.
Jez, April 2022