2. I am not sure. I think you should use it when it is really necessary and when you can not have ordinary enema. Still your body should to deal with its problems itself. Always follow recipe, especially as you know now that you can get constipated.
(I am 7 months pregnant now and I keep flushing every two months or so. I am a bit worried about Epsoms during my pregnancy, so I just take three Epsom drinks with half espom dose each, skip last one in the morning and do enema instead. It works just fine for me.)
3. I agree with Me_Fil on this one.
4. Stones will most likely keep building inside you. I am doing my 13 or so flush tonight (I started flushing 2 years ago). All previous once produced stones, except for my fourth flush (my first no stone flush, after which I switched to maintenance clensing every two or three months). I eat very healthy now but my body still produces stones.
My husband have completed about thirty something flushes (he started flushing 6 years ago) and eats the same food as I do but his last 5-6 maintenance flushes produced no stones.
I don't really know, perhaps my body will stop producing stones at some point.