I tried the script with a new version of calibre (0.6.13) and the script works, so there is no need to specify the noblr option. I changed the script in order to be able to share the same DB with different computers (no concurrent access, but hey!)
Code:
#!/bin/dash
# Batch File to start a Calibre configuration on Windows
# giving explicit control of the location of:
# - Calibe Program Files
# - Calibre Library Files
# - Calibre Config Files
# - Calibre Metadata database
# By setting the paths correctly it can be used to run:
# - A "portable calibre" off a USB stick.
# - A network installation with local metadata database
# (for performance) and books stored on a network share
CalibreConfig=/home/`whoami`/.config/calibre
LIBRARY_DIR='/media/Nicola/Ebooks/'
export CALIBRE_CONFIG_DIRECTORY=$CalibreConfig
export CALIBRE_LIBRARY_DIRECTORY=$LIBRARY_DIR
export CALIBRE_OVERRIDE_DATABASE_PATH=$CalibreConfig'/metadata.db'
echo CONFIG=$CALIBRE_CONFIG_DIRECTORY
echo LIBRARY=$CALIBRE_LIBRARY_DIRECTORY
echo DATABASE=$CALIBRE_OVERRIDE_DATABASE_PATH
cp $LIBRARY_DIR'/metadata.db' $CalibreConfig
calibre --with-library $LIBRARY_DIR
cp $CalibreConfig'/metadata.db' $LIBRARY_DIR'/metadata.db'