So it seems like most of the example code in the Build section is for the 1.x branch of MySensors. So does the Gateway also have to be running the 1.x branch?

If my goal is to integrate this into Home-Assistant, should I be using the 1.x branch, or 2.x branch?

Also, I've managed to follow the instructions on the Build site, and build myself a Serial Gateway. Which version of the Gateway code should I be using? Where would I find the serial gateway code for 1.x?

I also built a few nodes (not sure if that's what I should call them). One with a simple pushbutton, another with a motion sensor, and a third with a Temp/Humidity sensor (dht11). Now how would I get these connected to the Gateway? I think it's referred to as "Presentation", but I couldn't find much documentation on how to do it.

Just to confuse myself a little further, I found this section on the HA site, which talks about "Presentation", https://home-assistant.io/components/mysensors/#presentation

Would I be better off sticking to 1.x for now?
Is there some kind of step-by-step guide that I'm missing?

Please help, I'm sorry to throw out random questions, but i'm not sure where else to go.. Thanks..