The samples are just excerpts... I'm sure it'll be full on the actual album.
No, I'm not talking about a separate portion of the cue; I'm talking about an ostinato that played under the part that was included, under the sung melody. It didn't seem to be there in this version of the cue, so I'm guessing it was added for the library version. I think it's heard pretty prominently in "This Side of Paradise" when Spock gets zapped with the spores.