I've been a fan of the radio show A PRAIRIE HOME COMPANION for many years.
Unfortunately, in adapting his radio show to the screen, Keillor and director Robert Altman pretty much gutted everything I liked and replaced it with hokey country music, making the film much more like NASHVILLE (which I didn't like) than COMPANION.
There are many, many musical sequences that go on much, much too long. (Why is Lindsey Lohan singing???) The radio show was a variety show that featured eclectic styles of music including traditional jazz. The only jazz in the movie is over the end credits. The rest of the music is all country. In SHUT UP AND SING, I could tolerate the small doses necessary to explain the documentary, but in this film, it all seems out of place.
The thing I liked best about the radio show is Keillor's writing, very much in the style of American humorists and observationalists Will Rogers, James Thurber, Mark Twain, or Jean Shepherd. Unfortunately, there is NONE of Keillor's story-telling in the movie. Apparently, rearing that he has a face for radio, they made his on-screen involvement minimal.
The radio show uses certain set pieces like the 50s-style detective show-within-the-show, Guy Noir. Unfortunately, they bring this character to life and stick him on the stage with the real actors, who are even more real now as we see them backstage (mostly being boring). Kevin Kline does his darndest as Noir, but the character just doesn't work outside his universe.
Even worse, they create an angel (literally) for Virginia Madsen to play. At least Guy Noir gets a few chuckles; the angel takes itself so seriously it actually removes comedy from scenes that are apparently intended to be funny.
It's too bad this had to be the last film from the man who gave us MASH, and probably the only film from Keillor.