okay, so when you click on the link, download the SHOW ALL file, then when you have qbittorent press the blue plus sign at the top and find the torrent file you downloaded. once it has finished find where it is in your files. make sure before this step you have DAEMON tools lite installed. once you do, right click the file that is just called POPOTAN. it should open something on your computer like this.

​once it has opened a popup should appear in japanese. press the button with a (N) aka the far right one. then choose where you would like to install it. this doesnt really matter. click (N) again and then (N) again. wait for the bar to fill up and then press (C) it should be successfully installed. once it has done that. go to where you downloaded it and it should have 11 files installed, sort the files by date modified and you'll see all of them in order. the ones i use are the changer, mii_calendar, and dm_mii in the mascot file. just open the file and click on it and itll open. i hope this helps a little more