Just make some money, make sure you meet up with the women regularly and do not spend any time with devon if want love route. It can sometimes take a while to move forward but you will and they will get more friendly over time.
You can't miss anything unless you aim for that. There are events with both girls at almost every hours on every level, and you need specific stat points to unlock new levels. Kinda grindy, so just do the scenes until they are on repeat, then you can aim for stat rising only, or you can use the cheats to break the tresholds.
You got a save with the sister you can share. I can't progress with her for some reason. Probably corrupted my save by changing variables. Lol
I already watched the new scenes and progressed, so my save would only work for the new repeatable scenes if that's okay.
Nah, not yet. You don't see any change in their bodies yet, it's kinda like the "We just found out we're pregnant" situation. Probably will be included in one of the next updates.
Did you increase their lust or did you just make them hate you? Also, did you play arround with the script file? Cuz if that's fucked, then you won't progress (for example if u use an old i-patch.
I increased both their lust and relationship.. and no i didn't miss with any script file.
I've noticed the sister commented on mc's body, and the scene changed, after I'd worked out a bunch (at the pool). So physique is necessary too. And I'd wager work ethic is as well.
Ah, there is that one scene you have to repeat until they actually do it in Nicole's room. You know, where she refuses him at the start? Idk how exactly to trigger it, but repeating it at least a couple of times worked for me until she finally gives in.
This with change game to beter Thresome with pregnant Hot Ladies YES (if he ask for help share -You threaten him for stop NTR) 
I don't know what you mean, i've had payoffs with both mother and sister.
