I agree with Essie. Giv him a ring and say that you have your schedule (or you could do it casually by e-mail). Give him a few options for what works for you and see what he goes for. So "XXXday and XXXday evening, or XXXday and XXXday during the day. Let me know what works for you!"
And leave it to him to find something that fits in with your schedule, or to suggest an alternative. Don't worry about dinner being a bit too formal or anything like that. I think it's important to let him lead, which will be a bit uncomfortable for you, but a good 180, right?
On the 'single' front, I'd agree with Jeff. Vague is good. How did you leave that conversation in the end? Did you say anything?
And finally, don't worry too much about the interaction being perfect. You don't have to be perfect for your DBing to start working on B. You just have to be you, and to stay away from OR talks or anything that suggests sad/depressed etc!
