TRENTON A state appellate court has ruled that New Jersey's plan to curb development in the environmentally sensitive Highlands region can move forward. The decision made public Monday was hailed by environmental groups. They say it will help protect ground water from the 860,000-acre Highlands region that is used by more than 5 million New Jerseyans. Developers and affordable housing advocates had challenged the Highlands Council's master plan, which was adopted in 2008. They claim it does nothing to spur construction of homes or apartments for low- and moderate-income residents in the 88 communities in the Highlands region. The three-judge panel's decision stemmed from rulings it made in five separate cases that had challenged various aspects of the plan.