Main difference between a RIB for the UK and Med is deck layout. You'll probrably spend more time anchored than in the UK and hence want a sunbathing area, bathing ladder, shower and bimini (sunshade). In all my years of ribbing in the Solent I never needed any of these!
Medlines are popular but I'd imagine any UK manufacturer would give you the option of this sort of fit. I personally don't like the fitted bow anchor roller which some 'med styles' have. It makes bows to the quay more difficult and is in my view uneccesary for a small anchor on rope & chain.
ICC is a good idea but not compulsory on a UK registered boat. Registration docs (SSR) proof of ownership and insurance must all be carried at all times.
All the best to you Rouguey!
The South of France RYA Sea School