Margaret,
The reason you are confused is because CA tax is confusing. They want you to recalculate the federal return as if you were a resident for the entire year, then make adjustments on the CA 540 CA form for items not taxable by CA. They prorate the deductions and the taxes based on the percentage of income earned in CA.
As for the 3858, I think you have it right. She was in the state and did not have health coverage the entire time.
Sorry so late chiming in, I have been super busy and not been able to look at the board much.
Tom
Longview, TX