I can confirm Cookie's method of getting it to work. No offense though, Cookie, but you should have just posted it here rather, which I'm going to do. Seems pointless to go sign up for another board when this one is just as good for posting.
From Cookie's original post at WarezBB:
This is My Guide to Getting Guitar Hero 5 to load up useing Usb loader gx
Install this wad via wad manager
http://rapidshare.com/files/272838683/IOS5...-v5146.wad.html
its required to play!
Download Hermes IOS
http://gwht.wikidot.com/hermes-ios222-223
Im assumeing you already have Usb Loader Gx (latest Build)
and the Hombrew Channel installed
1. step load up Hommebrew Channel
2. start the cIOS 222 Installer
3. Read the warning message and push A
4. Select IOS249 to perform the install and press A
5. Select to Install Custom IOS 222
6. The Select IOS merged with IOS60 & 36
7. Let it Install and Reboot.
8. Open Up Homebrew Channel (may Restart in homebrew Channel
9. tart the cIOS 222 Installer
10. Read the warning message and push A
11. Select IOS249 to perform the install and press A
12. Select to Install Custom IOS 223
13. The Select IOS merged with IOS60 & 36
14. Install it
Now When you done installing it Open Usb Loader gx
now find Guitar Hero 5 and and Go to settings and select ios 223 and activate fix 002 and press b and then click on the disk and it should work.
Note that this is not mine, but Cookie238's guide, he/she deserves the credit.