I have the same issue as many other GMs. My players are not really interested in the temple, they want to fight Mistress Dusklight. So far they have bribed some city guards, gone around the city, cornered and recruited Aives, and found out about Delamar and Ruanna's plans.
On the opening night, they managed to split Delamar and Ruanna and set up Kalkek to eat Ruanna (when she tried to sneak around, she failed her stealth check). Added Muse Phantom and Lion Visitant. Phantom managed to possess two PCs and Axel before it was finally destroyed on the stage to the audience's amusement. Now they plan to track down and kill or catch Delamar(who managed to make it from the show back to the city alive despite their best efforts to quietly dispose him), infiltrate and sabotage the Celestial Menagerie show, find a way to frame Dusklight and get Andera to arrest her, etc.
Made temple connected to the valley(where the circus is) through the sewers. Made Kalkek escape from the CM through the temple and those sewers, so the party learned about the temple and the way to get there from him. Made Balleni (who escaped) promise a reward should they find a way to the temple for themselves and for her(and threaten should they not). Nevertheless, they are more inclined to trap and finish off Balleni and revenge CM, rather than investigate the temple.
Btw, even severe encounters in this AP seem to be relatively easy if the party just does not rush in and plan ahead. E.g. they carefully observed Will-o-wisp's island, hid in the forest around it, fireballed them, used the dust of appearance, and both monsters were eliminated in a couple of turns with minimum losses. The same happened in many other encounters, the party tends to ambush the enemies rather than the other way around.
