I did a network (ftp) install directly to Woody, with no problems. Just follow the instructions at http://cdimage.debian.org/ch11.html, but substitute
/dists/testing/main/disks-XXXX/current/ instead of /dists/stable/main/disks-XXXX/ to obtain the boot disks. The file install.bat should be in the base directory of the stuff you download. Run that from a dos prompt. You should probably have a look at http://www.debian.org/misc/README.mirrors and write down the addresses of a couple of local mirrors to make your installation faster (and to ease demand on main Debian servers). Bruce