...for the right movie at the wrong time.

In 1986 it was the intention of the ST-Filmmakers to have some fun after two somewhat brutal, dark or downright depressing films. And this is the main flaw of the film and, ultimately, the music.

While STIV itself is a worthy ST-Entry, it was simply the wrong film for concluding the loose trilogy it forms with STII and III.

As an alternate STIV, imagine a movie, darker than STIII with an epic story about a, say, political turmoil in the federation about the Genesis-Project and a glooming conflict with the Klingons and Kirks Rouge-Crew and their Bird of Prey caught in between to save the day. Included is a exellent score where James Horner expand upon his old themes and create new ones.
And now imagine a movie similar to STIV (with a Probe, Whales and all) in 1989 instead of the mediocre entry known as STV... do you get the point?

That said, the music by Leonard Rosenman isn't a good ST-Filmscore (although its similar to the music made for TOS) but it fits the movie: From the funny chase scenes to the atonal music made for the Probe or the Time Travel Sequence to the optimistic main theme... it fits STIV like a glove, although in terms of diversity, elegance and beauty, its no match for the compositions of Horner and Goldsmith. *** (** as an ST-Score)

(By the way, he didn't composed much music for the movie. All the tracks not included on the commercial release are short musical bits some 15-30 Seconds long. It's all amounting to less than 35 Minutes of Music heard in the Movie compared to the 27 Minutes on CD. Did anyone have any information about unused music?)