-N is capital it should be -n
jls@box:~$ importsce --help
Usage:
'importsce' with no options will prompt for characters of desired package name.
'importsce -f' to use a file list of packages - 'importsce -f FILENAME'.
'importsce -b' to add package to sceboot.lst.
'importsce -r' to use RAM for unpacking source debs.
'importsce -s' to list sizes of packages to be fetched and installed.
'importsce -d' to make use of existing SCE packages as dependencies. A select menu will appear.
'importsce -o' to add resulting SCE package to ondemand.
'importsce -N' for non interactive mode.
jls@box:~$