Thank you both! I wandered if it was path issues... or something along those lines. I will have to have a look when I get a minute.
I have placed it in the 'sprites' folder. I was wandering, once you have compiled a sprite, do you need all the pngs (outputted frames from another program) in the same folder as the sprite?
Basically those pngs are elements from which the sprite is created - does the sprite itself need to call those files in the same folder the sprite itself is located?
Thanks,