When the group is introduced to D squad around 7 minutes in there is a cinema in the background showing Back to the Future 4.
At the beginning of the episode, the four Sliders jump into the vortex, which is off screen. When Quinn jumps, he is clearly seen landing on the ground, getting up and walking away.
Nitpick: When Maggie breaks the man's arm, no snap is heard. If she really did break his arm in two there would be a sound.
This episode's plot relied heavily on the sci-fi movie Species.