Our BackTrack repositories keep getting updated with new tools, drivers etc. For example, we just added legacy madwifi-ng and r8187 injection capable drivers to the repository. You can follow these simple steps to add them to your iso, and keep it updated in general.
mv bt4-pre-final.iso ISO
chmod 755 bt4-customise.sh
apt-get upgrade && apt-get install madwifi-drivers r8187-drivers
echo blacklist ath5k >> /etc/modprobe.d/blacklist # In case you want to use madwifi-ng as default
echo blacklist rtl8187 >> /etc/modprobe.d/blacklist # In case you want to use legacy r8187 as default
The script should then run and generate the updated iso for you in /root/ISO/bt4-mod.iso.