I've got everything figured out at this point, except I just can NOT get emuNAND working. I tried dumping my NAND in Wiiflow Light to an external hard drive (because everyone insisted that thumbs and SD cards were a bad idea). The drive is formatted FAT32, 32k cluster size, one partition.
When I tried this on an SD card or thumb, it just dumped to a black screen and the system had to be hard rebooted. On the HDD it just dumps back to WiiFlow Light.