I use Pro Series, not ProConnect, but we have to enter two state wages boxes, one for NY(typically the same as federal wages), and the different one for NJ(includes Cafe 125 pre-tax health insurance, for one thing).

For the NY sourced wages, you must calculate NJ wages and enter both on the W2. Just be careful that NJ doesn't pick up BOTH amounts as wages, only the correct amount.

FYI, PA would pick up both, we just need to check a box to exclude the NY wages from PA.