Hi
better late than never... After several hours of trial, error, and avoidance of the thread http://wiki.centos.org/HowTos/InstallFromUSBkey, I was able to make this work using the following iso writer, which does some centos specific munging.
iso2usb-v0.7 http://iso2usb.sourceforge.net
It ran fine on Win7 x64, with an Airwave 7.3.5 64bit iso (what i needed) , filled it with the attached datafil.
Note that the server I am using always enumerates the USB as /sda, despite the defaults of iso2usb trying to suggest that you use /sda for the Hard Disk Name.
In the case that you have them back the front (as I did one time), or, your server put the USB at another /sdX entry, you can fix it when you see the error about the kickstart file which it will say should be at hd:sdb1:/ks.cfg , try changing it to hd:sda1:/ks.cfg
In the preceding example, after the : is forward slash ks.cfg, not a lower case L
hope that is useful
-jeff