Okay,
First of all, THIS IS SO COOL! You said you made this with the Godot Game Engine?! THAT'S AMAZING! I DIDN'T THINK IT WAS POSSIBLE TO MAKE SOMETHING LIKE THIS!
Secondly, I just tried it and it's pretty impressive: drawing pixels, choosing the colors for the palette, saving the file to the computer. It's all things I didn't think were possible to make in the engine!
Thirdly, I got a bit confused earlier with the save and export button
Overall, it's an amazing program!