Is it possible to use parts of the script at installation of packages? so that debian-packages could be installed on the 2gb-partition and symlinks automatically created on the 256mb-partition during installation? i think symlinks are the only solution for the problem with the small root-partition, without changing logical structure of the system (remove files for booting from /usr and move/symlink /usr to 2gb-partition) or bootloader configuration (to boot from 2gb-partition).