Invalid Image Size & Other Problems Options

[Apricot]

I just made some charsets using this generator thing, and I'm trying to import them into the program. However, I get the error "invalid image size" every time I do, even when I've pasted the image over some of the default sprites so I know it's the same size.

Another problem I'm having is that I'll make a sprite that seems perfectly fine, like this one for example

but when I put it in the game, for some reason it becomes this:


Can anyone help? It'd be much appreciated! ;w;