Now the weather has changed for the better. I've decided to get on with the cabinet.
My intention was to clean off the emulsion paint that some previous owner thought would improve its looks, then clear coat the original finish, unfortunately the plywood had started to delaminate and needed regluing, it ended up with the original paint flaking off where this had to be done other than that there was a good few coats of brushed on high build primer applied, that was then sanded flat
I am fortunate in having a great grandmother who is very skilled with the paint, (see avatar: that's some of her work on the Amîcaflex radio ) she showed me the method of recreating the crackle finish. That involves painting on the base colour then applying a clear lacquer, then, before that is fully cured a thin top coat of fast drying black celulose.
However, after the base coat and lacquer was applied, I thought the cabinet looked so good I'd leave it as it is, after all, it's less unoriginal that it was with that horrible beige emulsion paint on it!
The cabinet base colour is now blue again, though a much lighter and more cheerful shade. it may not impress the purists but at least it doesn't look ready for the tip.