First, thank you for the feedback.

"The animation was ok because it wasn't very complex."
-This project had a long development process, the animation does steadily improve with each chapter though.

"The lipsync needs work.
It was matched to the audio perfectly, but the mouths were just shrinking and growing larger very quickly in sync with the dialogue."
-Mm not quite, with the lip-syncing I was aiming for an "anime-aesthetic", so that it would be much easier to dub(especially into other languages). I can assure you the mouths weren't just "shrinking and growing", but I think you mean they gave you that feeling.
So alright, I'll try to do more varied mouth movements with future animations.

"The backgrounds:
It was colorful, but everything looked so flat.
Their was no detail."
-I wonder how or why you would think that.
Those backgrounds took hours to make, and there is no way all 6 locations(With one appearing 3 times, and improving each time.) had no detailed work.

I don't mean to be rude, but I don't think this was a real criticism.

"The characters:
work on your human anatomy, especially in faces.
They need a lot of work."

-...Did you even watch my animation? HOW is the human anatomy off for you? And did you notice how it slightly changed/improved through all 4 chapters?

"The dialogue was "corny", but the voice acting was good."
-Sadly I agree, but I learned from my mistakes and will never write anything corny in the future(I hope).

"This was bright, colorful, had a sweet story, but you need to make better character designs and backgrounds."

-I'm glad you liked it, but I must severely disagree and disregard those two claims.

Maybe you are on to something when you talk about character designs and background designs, but I cannot see it. I think the designs and backgrounds to a nice job and are well made for this project.

Perhaps if you could elaborate more on these two subjects, I could see what you are referring to more specifically.

Alright,
so what specifically did you think could be improved?