My two fingers are too tired, so here's a
link to a site that covers most of your situations and offers practical guidance.
My advice, is more fundamental, use your judgement in every situation and ride predictably, with clear (sometimes exaggerated) movements so that drivers know where you're headed and can adjust accordingly.
I also have something of a non trusting nature and generally prefer to cross behind rather than in front of cars, though I don't make a fetish of this.