We just use the CSV Builder, which can be run by the day, week, month, etc. or a range and exported. I do one each week for my detailed weekly reports as well as a monthly one for more higher level reports. The CSV takes just a little time to understand, but is very useful.
With the lack of documentation (not complaining!!!), I have found it's more of a trial and error when it comes to tags and groups and how they are used, unless you can VERY CLEARLY explain what it is you are trying to accomplish and the Samba geeks can lead you in the right direction.
Good Luck!!