Alo,
As we all say over and over, we are all different so what works for one may not for another. All you can do is listen to what others say but then experiment for yourself.
Having said that, for quite few of us simple PM by itself in capsule form, works, end of...
I've never tried the warm milk theory, myself. I'm not a great lover of milk as a drink by itself and certainly not warm milk and I can't stand yoghurt, so I don't bother and it doesn't seem to do any harm to my growth.
Timing-wise, I don't think it matters in the slightest on a 'few days at a time ' basis. There have been times when for various reasons I've missed a day or two and there has been no indication that somebody has stuck a pin in my balloons! I do try to maintain a 2000mg a day average, so if I miss the morning dose ( say) I'd probably take more that night to make up. I used to take mine three times a day but I found that difficult to cope with so dropped to twice a day. I normally aim to take mine at about 7-30 a.m with a cup of coffee ( I don't eat any breakfast) and 7-30p.m, about an hour after I've eaten, normally with a fizzy drink! The a.m ones I'm fairly consistent with, but the p.m ones can be any time between about 7pm and 10pm.
I buy 3 bottles of 100 x 500mg PM capsules ( I use Ainterol) at a time and they last me just over 10 weeks at 4 caps per day, average
I'm not going to get into a debate with Isabelle

but I simply couldn't be bothered with the supermarket stock of different things she takes, and I'd never be able to keep track anyway!
As far as we know at present, a maintenance dose is necessary for life, ( and your understanding of what that means is correct) but sfem is in the middle of an experiment to actually record the effects of dropping it completely. I suggest you find those threads and see where its got to, there is about a week to go I think.
As for progesterone, as Isabelle says it rounds them out, but it does that by developing ( swelling) the milk glands, so until the estrogens have grown you some, you've got nothing to expand, so there is no point in taking anything to do it! Estrogens and Progesterone are antagonistic, as well, so you shouldn't take them at the same physical time - in a natural female cycle the peak productions are offset from each other. Beverley Rose has recently started an experiment with RC to see what happens, and I am planning to start Progesterone cream, in a couple of weeks as an alternative, to also see what happens.
Hope this helps