I like the idea of it. Provides a nice little sandbox to test out sprites.
I did have some problems though.
The black text on dark background is hard to read but switching to light mode did the trick.
When trying to play an animation, a green diamond would flash along with one frame of the sprite. Which I found out was because I never set the number of frames. The complaint here is it’s quite jarring. Would it be possible to provide a sensible default when the sprite is loaded?
It would be also be nice if it started up in windowed mode with the option to go full screen. Rarely do I use applications in full screen.
Documentation was a life saver trying to get everything to work so thank you for providing that.