Hey guys,
I know how frustrating it is so count on me trying to figure what is happening!
- You don't need to change your DNS in our main router, just in your console it is OK (This is how I have it configured)
- To test if your internet have the correct MTU, go to a windows PC (not sure if linux is the same command) and on command promph (CMD.EXE) type this and presse enter:
ping google.com -l 1450
If the results displayed are like: Send and Received as 100% and Loss 0% it means your ISP (internet service provider) can handle packets with more than 1400 bytes so configure your Wii U with MTU 1500; Otherwise leave at 1400. Btw 1400 is the standard on ASIA ISPs as far as I know;
- Make sure you leave your WiiU in standby during ALL download and install process! While I was trying to install it several times the error always displayed like SYSTEM MEMORY 418 mb so something during the install process blows the WiiU memory. I had mine on standby for like 6 hours so I recommend you to do this when you go to sleep:
----- Just to make sure: Have your WiiU turned off for 1 minute then turn it on (just to clear cache or whatever it has on temporary memory)
----- Go to eShop and start the MK8 download
----- Go to WiiU Menu (home button) and check if at the download management if it has started
----- Turn off your WiiU (orange light shows it is on standby) and have sweet dreams 
----- When you wake up, turn WiiU on and a message like "Preparing" will be displayed, wait it to go away and you should see your MK8 icon on WiiU menu;
- How much free space do you have on your WiiU? I downloaded mine to WiiU memory (not sure if we can change this! LOL) and if was almost empty so if the instructions above don't work, how about clearing your WiiU memory? (make sure to have a backup!!!) It may work!
Let me know what happen!
Cya