Hi Isaac and thanks for getting in touch. I am aware of the difficulty of Windham allowing Tiny Houses from knowing the owner of Tiny Homes of Maine.
Unfortunately, Maine is a "Home Rule" state which means each municipality has the right to allow or disallow lots of things, basically they get to run their town without state intervention. There is a part of me that values that very much!
I've started working with Municipalities who are interested in having Tiny Houses in their towns rather than trying to work with towns who do not.
If I were you, I suppose I'd try to sell the lot in Windham, and look to purchase one in a town that you KNOW is open to Tiny House living (get that in writing) instead.
Probably not what you were hoping for in an answer, but seems like a good direction to go.