New Playwrights' Theatre is back at its Church Street location, with two new bathrooms to meet city regulations and a new musical by its talented composer Tim Grundmann, called "Eddie's Catchy Tunes."

The bathrooms work perfectly.

What Grundmann has unfortunately done is to write a musical about the problems of a composer trying to write a musical. All writers are eventually tempted to write about the problems writers have writing, and there is no dearth of poems about poets looking at blank paper, columns about columnists considering various column ideas, and songs about song writers mulling over song themes.

Just a dearth of such poems, columns and songs that are of any interest to anyone else.

There are all sorts of topics down at the bottom of the barrel - the unpredictable weather, the thoughts of your taxi driver - with a better chance of succedding. A funny line in this show, to those who recognize the reference, is about the bombing of "Platinum," a more expensive example of a worse show about the problems of putting on a show.

Anyway, in "Eddie's Catchy Tunes," there is this guy, Eddie, who wants to compose a hit musical, only he can't do it, and so he calls on his Muse, Calliope, and she writes a wonderful score for him, in between calls from Bernstein and Sondheim, and she's all dressed in pink and yearning for love, and so . . .

It has its moments. There is a charming version of the I'm-just-in-love song that goes "If I wake up kine of looney / And go out and kiss a Moonie," a torch song about a ravenous mosquito queen, and some Olympian jokes that work ("That must be the Furies - they get absolutely livid if you keep them waiting") among many that don't. It was not a good idea to mix mythologies, and have Mercury among the Greeks.

The cast, directed by Ken Bloom, has, for the most part, the winning enthusiasm that characterizes New Playwrights' Theatre comedies. At the preview, though, Eddie, played by Donald F. Campbell, was a lackluster hero.

Dana Vance has great comic verve as the Muse of Sport, when she isn't required to overdo the vulgarity, Jan Frederick Shiffman and Barbara Rappaport pich in spiritedly as a pair of actors, and Agnes Cummings makes the small role of Terpsichore absolutely adorable by doing it as a Helen Hokinson lady.