Thank you for giving me the opportunity to assist you. I will give the best answer that I can with the information provided.
1. Yes, you can use the insurance premiums plus all other medical expenses added together as a deduction on your NJ state return. NJ state limits your deduction to the amount in excess of your NJ gross income. If you are doing the return by hand, you must figure out the entry number yourself. For example, if your State Income is 85000, 2% of this is 1700, so 15000 - 1700 = 13300. If you are using software, enter your total medical expenses and the program should figure it out for you.
2. You do not need to attach or provide documentation with the return. In the event of a NJ audit of your medical expenses (rare) you would need to provide documentation at that time.
3. Yes, you are still eligible to efile or Webfile your NJ return with medical expense deduction.
Please let me know if you have additional questions.