What scenes from each Heroine's route must have happened, considering the storyline of Meikyuu and Rakuen of Grisaia?


In the second and third VN, they ditched the heroine's routes, but some
elements were used. So, excluding the H scenes, what other scenes/events must
have happened alongside with the common route, to explain the storyline of
Rakuen and Meikyuu?

For example:

> Makina learning how to operate a sniper rifle.

