You need to download both. Part 1 ends with v16. Part 2 is v17+. The reason moonbox did that was because the file size was getting too big and was going to be past the 5GB download limit of Mega.
Great game. The new update is awesome. Just 1 small thing I noticed in this update. In the scene on the elevator, the woman's panties completely change (color and style) from one shot to the next.
Hi. I've come across a bug or something. At the end of the conversation between Hikari and Akemi right before Hikari gets her 1st punishment, the game crashes and completely closes out.