There are lots of events to code and manage, yes. Several run at the same time and call others, and every animation (= every Show Picture command) has to be perfectly synched during the input phases of battle. I'd say the coding itself is not that complicated. Keeping track of everything is the real challenge.
During test play I found out that I have an easier time completing a Move's input sequence when I look at the battle animations and listen to the sounds of hits. Of course players can also do it by looking at the rotating square and key icon, but for me it was easier and more fun to look at the sprites.
I think it's better this way, because LoD's original square position (dead center on top of the sprites) often made it difficult to complete an Addition.