We went for the 5mins of age per month too - so we'd suggest 25mins few times a day, off or on lead.
Dylan is still on 3 meals a day - but only because he was getting really skinny - but didnt want to eat any more on his two meals a day. So we feed a cup full at 10am, 5pm, and then half a cup before bed which is usually any time after 9pm in the crate. We cant feed him any earlier than 10am as he wont eat it. He's an odd dog. We've cut down to two meals a day at about 7 months - and went back to 3 when he was 8.5months and on adult food. Once he starts filling out a bit we'll cut down again.
For crates, we didnt crate train Dylan until he was about 5 to 6 months, mainly because he was getting separation anxiety quite bad around then. He adjusted to it sooo well and because we kept the same bedding for a good month he knew it was his bed - and we also kept all his toys and his food and water bowls in it so its his little den. I personally think she could last the night without getting up. Dylan was pretty good by christmas, getting up at about 6-7am after bed at 9pm and he was only 4 months then. When it comes to bed time for Dylan, we feed him his final half cup, let him out for a pee, he never poos then, and he'll have his little wonder about and come straight back in - and he then goes straight into his crate. His crate is in the corner, and we have a fleece/blanket that covers the top and the longest side, and when thats folded down he knows its time to sleep - which works well when we pop out for a bit.
Hope that helps you out a bit! I bet Henry cant wait to meet his new puppy pal!