Number 2 above is the most critical. No matter how tempting it maybe, you must keep a clear seperation between company business and your side projects, always. If you are really concerned then I would go as far as not even mentioning it at the office, over lunch during the work day, or to any colleague you might want to work with in future until such a time as you are ready to sever your ties with your 9 to 5 career.