error 324 is a media issue, it stats this in the "wii cios error codes" pdf file
Error/issue number
ret=-324
Format/software
DvD backup
Clear text problem
Media issue
How to fix (if possible)
Don't use RW media!
You can use DVD+R or
DVD-R!
With DVD+R you have to
set the book-type to DVDROM!
Try burning media at
different speeds.
Try different media brand!
Update your CIOS!
EDIT: what error are you gettin when installing the wads