With regards the 235, it is not recommended to leave the boat on a mooring with the keel fully raised, as it make the centre of gravity very high and in extreme conditions, could be dangerous. The lifting strop on top of the keel has two eyes through it. Use the very first eye that appears through the cover to hold the keel. This way the keel is left projecting about 300mm below the hull and it keeps the centre of gravity that bit lower. If you are on a dying mooring, this small projection will slide up into the hull as she settles down and drop out as she lifts agian, maintaining stability.