Flashing on OSX

With software

Just do exactly as told for GNU/Linux, except for the part where you install dfu-programmer if you will, as you might also rely on Homebrew: brew install dfu-programmer

With avrispmkII and avrdude

# Set fuses (once)
avrdude -vv -p atxmega32a4 -P usb -c avrispmkII -U fuse0:w:0x00:m -U fuse1:w:0x00:m -U fuse2:w:0xbe:m -U fuse4:w:0xfe:m -U fuse5:w:0xec:m -U lock:w:0x3f:m

# Flash app and eeprom
avrdude -vv -p atxmega32a4 -P usb -c avrispmkII -U application:w:ChameleonMini.hex:i -U eeprom:w:ChameleonMini.eep:i