I had the same problem. If you hover on the excess SDI line on the form 540 form that you are trying to put zero in and it is red, then a magnifying glass opens a worksheet for excess SDI.
I filled it out for both my husband and I. We do not have 2 employers! But, it would only let me by pass it and get to a zero on the worksheet for excess SDI, until I put 2 employers on it! Then, it allowed me to enter my SDI from our W2 for TP (tax payer), SP (spouse) and get to the zero on the bottom line. The red 0 turned blue on the 540 form. Finally, filed my taxes.
