CatchBox destroy my sub Menü. Cant edit the Menu structure

Hi there, I have a huge problem. I run a WordPress 3.9 website and catchbox for our sport club (ts-schenefeld.de) is now already more than 1 year. So far no problems in recent months. Well, I have a problem that I can not understand. If I change just any point in my "sub-menu" (the menu right under my main menu), for example, remove an item, adding etc. and save, the menu has disappeared on the website and in the back is missing most of the menu structure. All gone ... I can not even create a new category to assign to the menu ... again the same thing problem. I have found that the Problem is on the catchbox theme, because if I change to a default theme and change something in the menu it works. As soon as I turn on catchbox change, the menu is destroyed again immediately. I also have all plugins disabled. Where it is not. I need every time again to import a backup to a site event to restore. I hope you can help me. (sorry for my bad english...i come from Germany) Thank you greeting Chris