As per post here: http://goo.gl/a2Z6g we are still having issues with users group function.
Basically, there are 2 issues:
1) When there is a Usergroup and one adds some members to it, if one of the members gets updated the whole UG would be resetted. Will end up with 0 users
2) If a member is added (through the Users page) to a UG, once another member gets updated, the UG will end up with only the LATEST member.
I have prepared a youtube video - which can be reached at : http://youtu.be/1HcXuzS1Gms [will be available in an hr or so - slow upload]
Hopefully this would give a clearer picture of what is wrong and can help us move forward.
Many thanks for your help
Wish you and your team a nice Easter