MP4 import

Cubase LE5 - came with Tascam US1800 interface.
Windows 7

I am trying to import an MP4 video recorded with my camcorder.

According to the tutorial, there is supposed to be a box I can check to “extract audio as separate file”.
This box doesn’t exist.

I can import the video and see it played in the small Quicktime box.
The video is its own track.

I have no separate audio track.
I cannot hear any audio being played.

What am I doing wrong?
Is this feature not included in LE 5?

Thanks

Bob S