Tren doesn't give me nightmares, just strange dreams as well. I use melatonin at 6mg about 30mins before bed, just to get to sleep. I sweat all the time so that is nothing new. I would say 75mg eod should be fine with the prop. I love tren\prop combo.
2.5 femura ed or eod is how I ran it, but haven't in a while so I can't say what guys are doing now. As for HCG, if it was me I would run it 500iu 3X per week on week 3,4,5 and then if you really need it after PCT.