Grab a copy of vmware player. Install XP in the virtual machine. Try vmxbuilder.com for building the virtual machine. Install Active Sync 4.5 on the Vm and you are set to go. When you plug your wizard into the PC, if the VM is in the foreground the usb will be redirected to the VM instead of windows 7.
I have been using this method to flash my wizard and has never failed. Much safer than a 50/50 chance of bricking your fone
Samsung Galaxy SIII
OmniRom 4.4.1 Nightly