Yes - you should be able to simply put any bash commands you want to run after the installation is finished in the "%post" section of the kickstart file. It's helpful to set up some logging of it so you can analyze after the fact what it did and didn't do.
%post --interpreter /bin/bash
#Install wget, because minimal doesn't come with it
yum -y install wget
cd /root
wget <YOUR SERVER>/file.tar.gz &> kickstart.log
tar -zxvf file.tar.gz &> kickstart.log
cd file &> kickstart.log
echo "Now making...." &> kickstart.log
make all &> kickstart.log
%end