All worlds complete (not all custom parts are collected, though), good ending has been obtained (can watch again from shop). If game freezes at load, reset and it should work fine. This if for the US version of the game for Project 64.
I don't have a wii u anymore to test it myself, but if homebrews are not visible on the wii u menu I think you can press L + R + minus to open the plugin menu, there should be an option called "homebrews on wii u menu" or something similar
Or when your player dies, you can say in code, if enemy exists, do nothing, but if enemy does not exist, then create enemy at certain spot. (This would be a pain tho for lots of emeies)