Note: if using modern Ubuntu or Debian 32-bit, first do: sudo apt-get install lib32gcc1

wget -c http://storefront.steampowered.com/download/hldsupdatetool.bin || exit
chmod +x hldsupdatetool.bin || exit
./hldsupdatetool.bin || exit
 
cat <<EOL > go
cd system
./ucc-bin server KF-BioticsLab.rom?game=KFmod.KFGameType?VACSecured=true?MaxPlayers=6?GamePassword=XXXXXXX?AdminPassword=YYYYYYY?AdminName=admin
EOL
chmod +x go
 
echo './steam -command update -game killingfloor -dir .' > update
chmod +x update
 
./update ; ./update

Get steam:

wget http://storefront.steampowered.com/download/hldsupdatetool.bin
chmod +x hldsupdatetool.bin
./hldsupdatetool.bin

Install:

./steam -command update -game killingfloor -dir .

The launch script implicitly configures it:

cd system
./ucc-bin server KF-BioticsLab.rom?game=KFmod.KFGameType?VACSecured=true?MaxPlayers=6?GamePassword=XXXXXXX?AdminPassword=YYYYYYY?AdminName=admin