Hello!

We didn't finish with manual yet, we are working on it and will try to release during this month.

About how to add new action: we have added interface which allows to add new actions, but it can be used by persons who know the structure of the UNA code. Points System bases on Alerts (it is special code) which exists in most part of the modules module and allows to catch modules' activities. So, when you add new action to Points system you need to define correctly the name of the Alert and action and then define participants to assign points.
If you like I can describe how to find the Alerts in the code.

By default the all modules' Alerts exist in Points System with parameters and you just need to set points to earn for members.