I used to do it off stokes bay and lee-on-solent. as long as you are a suitable distance off the beach i don't think it matters. we did para sailing and banana boats as well.
Might be being silly but they are supposed to be stiff to tighten. Effectively you are tightening and releasing a nut.
The tighter you want it the harder it will be.
Most of the rules are worded
No liveaboards ..... however the company may wave this at its own discretion.
I know a few people who live at haslar marina, and i know there are livabords at gosport marina as well.
as i understand it the Marina is not breaking the law.
They can only charge what they pay for the power.
But they can charge you what they want for the cost of supplying it. Maintenance etc...
Kingspan is a foam insulation board used to line the cavity of new houses.
Im gonna take a stab and say the owner is a builder most of the materials and fittings are household and not marine.