I'm having this issue when re-hacking my Wii. I used ModMii to download all the necessary files that I needed including both USB Loader GX and WiiFlow. It came with a USB Loader forwarder WAD, and I installed it but it doesn't correctly boot to the USB Loader app on my USB. I tried a separate forwarder WAD for Wiiflow and it does the same thing. Forwarders work fine when the apps are on my SD, but then they won't let me select the USB Drive to see my games. How can I direct these forwarder to the apps folder on my USB Drive?