blieshound,
I have an engineering firm in NY and I would follow David's advice in talking to the state board.
I looked again at Article 145 and found the following:
§7201. Definition of practice of engineering.
The practice of the profession of engineering is defined as performing professional service such as consultation, investigation, evaluation, planning, design or supervision of construction or operation in connection with any utilities, structures, buildings, machines, equipment, processes, works, or projects wherein the safeguarding of life, health and property is concerned, when such service or work requires the application of engineering principles and data.
My opinion only, is that the law is more than about someone getting hurt as property is also mentioned. Again, my non-legal opinion is that if you design a system (I am not saying manufacturer or build) and there is the possibility of property being damaged then it falls under the practice of engineering.
If you are offering only consulting/design services then the safe way is to set up a PLLC (not an LLC), LLP, or PC. You do have to be a registered engineer to set up a PLLC in NY.
Definitely talk to the state board and have specific questions for them and tell them exactly what you business will be and who the expected end user's are.
Good luck.
Patrick