Hiya, thank you so much for the purchase, it's much appreciated~ I'm super glad to hear you enjoyed the game, too and hope you'll enjoy the future chapters to come. To answer your questions:
1 - If possible, I'll offer the final combination of all the chapters to all those who own the seperate releases but would need to explore options for how to do this. So can't say anything solid for sure yet!
2 - For the last CG scene, you have to favour Tari at every chance you get while snubbing Jilly, and the scene happens fairly early on to replace another CG scene. Hopefully that helps~