Thanks again. In this case, it will be easier to handle it slightly differently and use sprites.
Just thinking of future examples though (and trying to improve my understanding of what is possible and what's not in C3), for example, if you had an image of a till, or a calculator. It'd be a pain to draw all the individual buttons.
Is it possible to get the x,y co-ordinates of a mouse click / touch (will be a mobile app) in the event sheet? You could then carry out the action dependant on the exact location of the touch on the image (which would still be a sprite object, just a large one) - i.e. if x is between 10 and 30 and y between 80 and 100 you know that it's the area of the image that equates to the plus button, if it's another value its this button, etc etc?