I can't seem to get the button to show after completing a campaign map to show the next map ( and I did go through the campaign and not just select the map by itself ). I have compressed the campaign and maps into a .rar file and have uploaded it so that you might be able to see what I'm doing wrong. ( Since you mentioned that would help. )
Please note that it does not exactly follow what you did in the tutorial, for even when I did what that said I was unable to get Map02 button to show, even after making the button for it. I have gone through the tutorial, and when seeing that that section of it ( the linking part of the maps ) didn't work, I made this campaign to see if it was something else wrong.