I've updated the Sprite Exporter with some requested features and some fixes (see changelog below). I've also released the source code for the Sprite Exporter so anyone can make their own changes to it. The code is a bit of a mess and there is zero comments, but hopefully you can make sense of it.

Changelog:

• Generated C code is now a const array
• Generated code is now indented with a tab instead of a space
• Extended the zoom limit to 10x instead of 2x
• Colors that share the same index is marked red
• Drag and drop of bmp and png files should work more consistently
• Fixed spelling mistakes