The xcc_mixer.zip file you have requested: Utilities / XCC Mixer - 650.42kb is not available. Perhaps try browsing all files for the game C&C: Generals Zero Hour and upload any files you want to share or are missing. This is the only information we could locate:
Check the readme below for info, it doesn't say it supports CnC Generals in the readme but it definately does :)
XCC Mixer 1.23 has been released. Support for Generals has been added. BIGs can't be edited yet (that's for 1.24).