For chapters 7 & 8, regarding the append quests which most are time-limited and linked to each other, I just gathered the materials before starting any of the quest chains.
Only danger is accidentally triggering a chain, best is to save at the very beginning of ch.7 and go over your inventory and the quest lists for those two chapters...
For materials needed, look here;
http://kamidori.seiha.org/index.php?title=Quests