Egomassive should have an actual answer to this.

In the meantime since I'm here, try this.
1. In your "World.ini", in the [World], you should find "Character= Juni" tag. To change the initial character, simply change "Juni" to whatever the file name of your character is- "File's name. file extension".
 If you haven't already, before that, you need to add your character's .png file into the "Custom Objects" folder in your world's file. Afterwards , write in the [Custom Character] "Imagen="File's name"."file extension" (where as n=any number, file's name is the name, and file extension of the image which I presume is a .png). If your custom character is unintentionally invisible, you've done something wrong.

2. I'll leave it to him.

 Well, good luck.

I'm thinking if re-creating an old level that I've made. However, I was wondering if "Ks Ex" has a feature which "KS +" has - An overlay tool, using the Layer 2. I want to deter from CO's and templates because CO's have a 255 object limit, templates have 200, well I'm not sure?  Why? I want to have foreground tileset blocks without worrying about the restrictions.

An unrelated question, but is there a program that I can use online that helps with using the script.lua? I'm using "Notepad ++", but I'm not sure if any programs do the job easier.

As you can't already see, I'm very new to this mod, but I want to try tackling it after years of staying away from it.

It is a really complex matter. When you are talking about an iconic character, even if the sizes are different and you made the art entirely yourself, it is still considered a rip-off, and the original author can claim that you've stolen his idea which falls under the copyright act.

Mario is a very iconic character for 2 reasons.
1. Almost everyone will know who Mario is and will be able to identify him.
2. Almost everyone who knows Mario will also link it directly to Nintendo, the same way Sonic is linked to Sega.

So the problem is, that when you use such iconic character, people will automatically assume Nintendo was involved somewhere in the process of making it, or even worse, think that it was made by Nintendo.

This last one is where most lawsuits come from, especially if the end product is of poor quality.

  Thanks you two, but LPchip. Does this apply to both the character and the graphics of the specific game? I might have read it incorrectly but it post seems to only apply to the character.

   Now on a completely unrelated question because I do not want to bother creating a new topic because I'll seem personally awkward to me.
Are these considered Knytt Stories bugs?
 There are 2 bugs involved with the objects in the Bank 2 Object 18, 19 or who I called them, the Thunder Relics.
Its too hard for me to explain but I'll try to explain it in steps.
1. Let Juni activate a shift that takes her to a screen with those 2 Object. If the shift brings her within the range of their attack box. They'll unleash their attack, but Juni would'nt get hurt.

2. In KS+, Make Juni use her hologram. Then, make Juni trigger a trigger that spawns a relic with the hologram within it's attack box. The relic will unleash their attack and it will hurt the now invisible Juni regardless where she is on the screen.

So are these 2 bug? Or is it just my files?

  Thanks, but I'm probably going to give up on trying it. I might try to use KS Ex someday but at first glance it looks far too complicated for me. Also, I've grown attached to Egomassive's mod for it's simplicity and I couldn't sacrifice the triggers and it's use of having custom objects behave like objects in vanilla KS. Still, the rising lava in your demonstration example is what I need for my world. You two have a star.