Here ya'll go gamers cause i find myself replying really late
Decoded version of the 'gibberish' Zu says at the end of the 'flashbacks/dreams' (using vigenere cipher)
1st flashback: (this part uses ROT1 instead of ROT0) key: MAGENTA
normal: Zu: v tlj miv apd
decoded: Zu: i see you now
2nd flashback: (ROT0) key: NBHFOUB(i think), the rest are the same
normal: Zu: boj j w mbj zvz pygbsl rs c srbsngye lpb bslf zz ztif bae td vybeu.
decoded: Zu: onc e i saw you before me i realised you were my soul and my heart.
3rd flashback:
normal: Zu: gihsy sph gvw pljahpsu gf voat hbjf xvwzx. j jjsq ziwr zvz tisrwlw
decoded: Zu: thank you for bringing me into this world. I will love you forever
4th flashback:
normal: Zu: v bt gswpzjul pyugfy oimu spy dco bef fti jsbvk tt gf zz stjy
decoded: Zu: i am becoming better just for you are you proud of me my love
As for the endings, it would really help if you gave me which specific ones you needed help with, because i dont have much time to make a guide on all of them, sorry for the trouble!