As for how the logic works in this game, once a wall is completed, every BALL flood-fills its area, marking it with a number.  Anything that has been marked is kept clean, and anything not marked is set as solid.

Ah! That's really smart!  It's quite literally thinking outside the box

That reminds me of when I was working on Puyo Puyo.  I couldn't find any algorithms published for how to detect if 4 or more balls on a grid are connected 4-directionally and it took me months before I figured out a way to do it.  You just detect all the balls that form chains of 3 or less, which is easy since there are so few combinations and they're all trivial, and then just destroy everything else.

Same here, I hopethey all get finished. And nice job on the filling in Xonix.

Lols this is my thought process whenever I try to restart this:

Ok this is basically finished, time to wrap it up
Hmm i need to add powerups just like the original
Uhoh I only have 4x4 sprite options
Uhg this is impossible, they all look the same
Maybe 8x8 and have them take up 4 tiles?
Bleh then collision gets even more wacky
8x8 is way too big anyway
Blarg
I'll work on it later

Builerboy, I loled.

This is an awesome game! hope you finish it!

I hope you release this at one point Bboy