Thanks for the chart of Accounts list. I don't have designation but I do have some accounting knowledge enough to go through B/S and Income Statement. My guess is the S141 details just to assure that the Tax file would not done by somebody with so little accounting knowledge which could end up in a mess.

I expect that CRA is quite accustomed to messes. 🙂
You would fill out S141 as no designation and connected to the company.  No Notes, and pretty much no to everything else.  You should be fine as long as your assets equal liabilities + shareholder equity.  Holler if you run into any issues.