[Scripting Question] Diamond and Pearl styled HP box

I was making a DP styled HP box. But there is one thing that confuses me.
The HP bar does not seem to look right and there is one line missing from the bottom.

So here is my question: How do I resize the height of the HP bar to make it look like DP? And how do I get rid of the black bar that appears every time a Pokemon takes damage?

Any help would be appreciated. Thanks. :)

Have a play around with some of the Values in the script PokeBattle_SceneConstants