I had a quick look at the script you have linked to. It says "WARNING!! EXPERIMENTAL SETTINGS" and something like "install it and believe it", not very helpful. To understand what may going wrong I have to dive into the scripts and analyze them what could going wrong. Instead of doing this I would suggest to use a tested and stable script that is more transparent what it does. I use one that answers [How do I make the OS reset itself every time it boots up?](https://raspberrypi.stackexchange.com/a/85569/79866).