Its not the game itself. See above. Its a systemupdate of WiiU (which contains the netcode of WiiU) and which has problems with communicating sometimes with the ARM-dualcore-cpu - when for example playing a game online- at the same time downloading a big game (which then has to be uncompressed, installed etc) Now got it? Thats it. Happens everywhere with Apple-Iphones and Ipads as ARM cpus are sometimes problematic.
So you don`t have to update your game. The game itself is fine and does not have any bugs. The WiiU itself has a bug. This has to be fixed. To do this you buy a new game and this will contain a fix for the hardware- or you download it with Internet.