Realistically, I could see the French Empire being largely dismantled and divided by the CP, while Britain only loses Egypt, Kuwait and Sudan, which are returned to the Ottomans. Russia totally collapsing isn't going to happen, as long as the Germans don't send Lenin from Switzerland to Russia, but there would be a severe internal struggle, and we could still see the rise of a USSR-like state...perhaps run by the Mensheviks?
No matter when the Germans win, Britain will not lose any colonies because Germany has no cards it can effectively play. The submarine threat in World War One was short-lived while there was even less prospect of a succesful invasion of Britain during World War I than there was in World War II, simply because the Germans had no air power to even the odds slightly, which wouldn't have helped them anyway.