Please have a look on the attached pictures.
You have to adjust the blue graph (in settings window), so it looks something like on the picture. Most of the time, I was in deep and light sleep, but sometimes I also moved around a lot which could be interpreted as being awake. If the blue is always is the upper half, then you might have to lower the scale value.
After that, set the trigger level to somewhere around upper part of light sleep or awake.

On the 2nd picture you can see the improvement with the new trigger algorithm. Before you would already have gotten woken up at the first yellow spike, now it takes a bit more. With the new algorithm I hope to have improved the way it detects the right wake up time.

If you are struggling to get it working, please post a picture of your record here and we can try to help adjusting it.
In case you are not aware of it, SleepAnalyser has a nice export function to export the graph a you can see it on my pictures.