lighting board

It's really hard, as I guess you know , to find clear information. But I've found the following (which may or may not be useful to somebody in the future) and it seems a waste not to post it :-

You don't need to register a trailer less than 750kg to use it in EU (from .gov so is good info).

As a visitor you should* be fine towing abroad as long as your trailer is under 750kg and conforms to the relevant UK regs.

If your trailer was built after about 2002 (I seems impossible to find the date the new EU regs came in) you must use the poles to mount the lighting board**, if you trailer doesn't have fixings for the poles it's pretty safe to assume it was built before they were a requirement and you will be ok in the UK.

* This is anecdotal so, while worth mentioning, may not be 100% reliable.

** My Blaze trailer does not have fixings for poles and the boat was new in 2002. I think I would continue to use the pintle mounted board in the UK if I bought a boat with a newer trailer but would accept that there is a small risk go getting a pull from the boys in blue.