A sequence was filmed featuring the Alien outside the Shuttle enterance which was cureled up before it slowly rises up to look at her:

A segment was shown in "The Eigth Passenger" documentary on the quad features, but they onlt show a segment of the scene.

Went searching for a larger verison of the magazine cover a shot of this was featured on and found this extra little segment not featured on the Quad, Saga, Laserdisc and legacy features:

RARE ALIEN SHOT from xeno_alpha on Vimeo.

Thought id show it for those who are intersted :) it's only a short clip which i slowed down a little.