Does anyone have a save either at the end of Ch. 4 or start of Ch. 5 on the MASH route? During my playthrough I somehow messed it up so I was strict ASH route but the ending of just MC and Sadie on their own so I'd like to see the ending for all of MASH
There isn't an ASH route, so I figure you were on both HA and Sadie Solo routes, when it comes to Ch5, the solo routes take precedence, if you're not already locked down (for most of them, you should be locked down, but there isn't an "exclusive" conversation with Sadie on her route).
To add Mora, you need to invite her in when she delivers pizza at movie night (you need to have the minimum points criteria for her to accept, I think it's Heidi 8, Athena 8, Mora 3), and invite her to move in with you after meeting up with her ex. There's other bits that should be obvious when they come up, as with all of them, but I think those are the two critical points that you can't afford to miss.