IOS249 is only used as a support IOS for backup launchers.
Games rely on many IOS files.
WiiWare especially relies on IOS53 and IOS55, as well as IOS56.
Edit: I'm not sure if there is an easy way to inject an IOS into a NAND backup, at the moment. Seems you're better off making sure you have...
Just saying hi, as my friend finally prodded me to create an account. I've been hacking the Wii for some time, but don't really bother to post on message boards. I'm more into hardware hacking than software hacking (not modchips, mind you).