I can not change the pic of the ? in the GUI!!!
Yes you can.
a) we already have someone on these boards go by bigbrother, so please choose another handle
b)you obviously did not read the forum rules, as you did not have a descriptive topic. they are used for searching forums, and helping people, even after this thread is technically done.
c) way to give us any information at all to help you with your problem.
I would almost lock this, but since it is such an easy solution, (most likely), and if your next post is in a calm and adult manner, we can keep talking.
Now, let us know what exactly your problem is. Did you load a correct sized image into your sprite manager, and then go to your gui and change "Background Image"?