The Canadian guys are best placed to answer this but I don't think it's a huge area for concern with relatively mild UK temperatures, and particularly with multi-grade oil, if used.
I can remember starting O-200s with a squirt of ether, because they simply would not start on avgas due to low ambient temperature. No hangar was available. Ether's risky if used in excess but I don't think the bottom end suffered.
The biggest issue with startup lubrication in my mind isn't cold weather - it's loss of oil pump prime with some engines (Continentals especially) if they're unflown for a period... And the attempts to start them before prime is re-established.
Whatever Lycoming suggests, don't let those knuckle heads at EASA find out!
