How can I fix my wm 602 washing machine?

In the previous washes there had been sheared plastic shreds on some of the clothes and in the filter. Also been a few visible leaks. On removing and taking apart the front of the drum looks to be plastic with a gap filled with some kind of seal. I expect you would fill it using a special resin and silicone gun. Anyway this seal has degraded and is definately the same as the debris inside the drum.

Am I on the right track. Can anyone advise how I take the machine apart further to clean bits and what material I can reseal with. On the last wash the machine was working ok but made a few bad banging noises when spinning. Could this debris be jamming or blocking anything?

Is this something that would be best done by a repair engineer? How much is it likely to cost. I'm in Burnley, lancs, UK.
Cheers!