well my wii couldnt even read my official GC games until i uninstalled DM lite for some reason so yeah maybe try installing the official mios?I thought it has something to do with my wii which doesn't be able read dvd-r without Neogamma rather than a nintendont bug.
I always used default setting and selected sd(which had nintendont,game folder(the game iso wasn't there),and memory card) (and the sd has 1.83 GB space ).
downloaded the new version of loader yesterday and it was what i used and before that i think i used a version from 2-3 weeks ago.
I also used imgburn for burning and burned at 3x(lowest burn speed of my dvd-RW) on a Princo-Budget DVD-r.