I can't speak to your specific flour but I have worked with coarsely ground whole wheat flour.
My standard bread recipes required quite a bit more kneading than usual. Additionally I had to work with them while they were still quite sticky to eventually get them to an elastic consistency.
I use a stand mixer to do the kneading for me- I'm afraid that it would be quite a mess doing it by hand. Remember that, when forming gluten, you can always trade work for time. If you can't find finer flour then I would recommend kneading the dough as much as you are able, let it rest for 15 minutes so the proteins relax, and then knead it again and see if you can't get the consistency you want without kneading all day.
Make sure the flour isn't so coarse, or has shards or bran, that would actually cut the gluten and prevent it from forming sheets. If this is the case then I don't know if you could make bread out of it predominantly. Perhaps if it were soaked overnight as in a poolish?
I mill my own flour to the finest possible setting and this seems to produce a much better textured bread.
As for the lack of rising and yeast- it is the same problem. Yeast are perfectly happy eating damaged starch in your flour. Adding sugar wouldn't necessarily help. If your dough was not elastic and failed your window pane test then there is nothing to really hold the structure of the bread. Your yeast may have been going crazy and there was just no balloon for them to blow up.
I'm new to the site and I wish I could make this a comment, not an answer, but I don't know how.
Hand pulled noodles use cake flour with less gluten and baking soda to reduce the gluten even further.
http://www.youtube.com/watch?v=Ze2SphqrWyg&feature=g-hist
http://www.youtube.com/watch?v=nBSTSKY_DQs&feature=g-hist
If you are hand kneading, it's unlikely you are over-kneading because the dough will become very hard. The issue is very likely the soda ash overreacting with the wheat. But if you did over-knead, there is nothing you can do to save it
If you did break, there is no way of fixing it. Maybe to save the dough, change the strategy: Add eggs and more flour and make egg pasta. I have over-kneaded egg pasta many times in my KitchenAid mixer and it still turns out alright.
Best Answer
Gluten is what makes a dough stick together and have structure. Coconut flour has no gluten, so the resulting dough will be a crumbly mess. Intentionally gluten free recipes usually contain any number of special additives to compensate for the lack of gluten.