Explosive graphics?!?

[Tenkarider]

Ok... shit happened.

I was using FF6SE to replace/add new graphics, i replaced what i didn't like until i could... then i did it: i added some new image in the moster block.
When i tested a certain battle, the game crashed as soon as the added sprites appeared
I thought it was a matter of moulds or battle events conflict, until i tested those sprites in a random battle: crashed again.

Then i realized that there are only 147 images for monsters, starting from 148 there are Ramuh and the other espers + some other sprite at the end of esper list.
If i add a new image to mosters list, then(according to the current position of the image list) the new image is inserted right after the current image, the following images of the list increment their number. The same happens for all the images used for esper list.

So i thought if you go over image 147 for monsters, the game crashes, but it's not exactly that:

- Replaced image 147 is fine;
- Added image 148 crush the game;
- Added image 149 crush the game;
- Added image 150 crush the game;
- Added image 151 is fine O_o ;
- Image 152 is now the current number of Wrexsoul's minions and is fine.

Espers are ok, so only those 3 images gives some trouble, but not all added ones.
I also tried to change moulds and palettes of the 3 images... nothing.


Could anyone have any kind of clue? what decides if added images are ok or not? or what restrictions there are on the image list?