@RobJoy
I think you should start with the "All-In-One" pack and adjust after if needed.
At the end, you should have:
Act 1 is separated in 3 parts:
Act 1 .1 fix (My_Legacy.exe)
Act 1 .2 (My_Legacy_Second.exe)
Act 1 .3 fix (Ethan_Legacy_Third.exe)
Then, you have an optional extra "The morning glory" and a so optional IF "The new model".
Extra
(Ethan_Legacy_Morning_Glory.exe)
IF
(Ethan_Legacy_New_Model.exe)
Act 2 and Act 3 are NOT separated in parts. You'll just have to play the last versions of each, plus an extra after Act 2.
Act 2 v3a (Ethan_Legacy_Fourth.exe)
Act 2 Extra (Ethan_Legacy_MovieNight.exe)
Act 3 v4SE (EthansLegacy.exe renpy game)
Saves are not used between Acts and parts.