How to setup:

1 - CLone the code and add project in unity hub.

2 - Open, go to folder "Resources" and add a folder "Sprites/Fish", or just update the patch in "Piece.cs" line 49, the code "string folderPath = "Sprites/Fish";", add all images here.

3 - Set all images to "Sprite (2D and UI).

4 - Set to true in all images, this option "Read/Write", if not activated, the code won't work.

5 - Click on play and test.

6 - If the divisions between the images are not appearing when you start, go to the following object "Canvas" and then to its child "Panel_3x3", see if in the grid layout group in spacing the value is non-zero, if it is zero, test 1 or 2.