You can use NeoGamma, unless you updated cIOS38 to rev15 or higher.
You can install cIOS222, 223, 224, and 202 for full compatibility with the USB loading credentials.
I use Uloader for disc launching and USB Loader GX for USB loading.
PM me for a Wii downloading sight.
Also I'm working on a Wii technical help thread.
It's on another forum though and is only in it's infant stages. :P
You'll need to update cIOS38 or you can update cIOS222... :)
I would personally do IOS222 installer.
http://filetrip.net/g25123280-hermes-cIOS-Installer.html
download this file and unzip it.
Next, there is a folder inside called apps.
put the contents of that in your /apps folder on your SD Card.
Next run the cIOS222 installer
-choose 249 as the default thingy at the beginning.
-install each cIOS from the list.
-use the recommended installation for the first 2
-the last 2 will not have a recommended on it.
-just use the IOS that it lands on when you click the installer.
Forgot to add this... :P
Spoiler
then unrar the file to a folder called uloader.in it is a folder called "wbfs_win", Open that folder.then there is a program inside of it called wbfs_win.exe. open this file.select your flash drive letter (if you don't know it, go to My Computer, then see what drive your removable flash drive is. if you select the wrong drive, you may format your hard drive.... :POnce you select your drive letter, there will be some options on the bottom of the window. they will say something like 1 --> add, 2 --etc....don't worry about the rest for now, just press 1 to add a game to your flash drive.A window will pop up and navigate to the Super Paper Mario.iso file and click add or whatever to save it to the flash drive.it will transfer only the game. i think it's like .43 gb or 430 MBs. So it's not that big.you then just exit the program and then safely eject your flash drive from your computer.Then plug it into your wii, launch the HBC and select USB Loader GX or Uloader (i prefer USB Loader GX myself....looks nicer than Uloader!!) then choose the game you want and BAM!!! You're playing Super Paper Mario from your flash drive!!
hope it helps!
You can also update cIOS38.
, but I suggest until waiting later.
you can use this = http://filetrip.net/file.php?id=9426
download that, unzip it and then put it into the /apps folder on your SD Card.
-run it through the Homebrew Channel
-select IOS249 as the default.
-then switch the installer to Network installation.
It should work.
if you need any help, just let me know.