Can Cartwright save his novel The Promise of Happiness by getting his plot moving?

Yesteday's post noted that Jaustin Cartwright's 2004 novel, The Promise of Happiness, gets off to a great start and is an excellent novel "so far," thati s, through the first 60 or so pp., but today I have to note that, like so many novels, it seems, this one begins to founder once the write establishes the fundamentals elements: character, place, setting (time), tone. Cartwright began w/ a great premise - a family of 5, based in England, awaits the imminent release of eldest daughter serving a 2-year sentence in a NY state prison. We gradually learn the details of her arrest - it involves the sale of stolen artwork - but now that she's out of prison (her younger brother, Charlie, has traveled to NY to pick her up at the prison and bring her home to England) the novel founders. Charlie and Ju-Ju (Juliet) take a meandering course homeward, visiting Buffalo, the Finger Lakes, Cornell, now heading toward the Hudson River Valley - all of which seems ridiculous and improbable and does not advance the story line in the least, which I could still accept if there were some real insight into the upstate New York setting, which there is not, just a sequence of place names and some condescending descriptions of the working-class people in Buffalo. He's got to get this plot moving! One of the potential strengths of the novel comes from Ju-Ju's (and ultimately Cartwright's) knowledge about art, in particular the stained-glass work of Tiffany (and La Farge), and many of the passages in which Ju-Ju opines about the stained-glass are quite smart, if, in my view, off-base about why these works were so popular in the U.S. ca 1890; less compelling and less credible are Ju-ju's ruminations and discussions about why she took the fall and went to prison while her partner - for whom she seems to have nothing but contempt - took a walk. A lot of things just are not clicking. That said, Cartwright's strongest character is the moody father, Charles, who awaits the return of the Prodigal Daughter (yes, Cartwright makes the connections between the daughter and the parable and the stained-glass representations) Juliet - (while indulging in some infidelities of his own) - he is the lead character and in some ways the heart of the novel and his reconciliation, or not, with his daughter is the scene we're waiting for; if Cartwright can get us there and bring the scene off, all will be redeemed.