Ok. English is not my native lang, but I’ll try.
I have site hackday.ru
At site I have Events (HackDay’s):
Every HackDay is a single event with separate auditory.
Every user can join to any event.
Membership of user in event I checking by:
1. For every event there is unique usergroup: http://s3.amazonaws.com/floomby/8_11_2010/z2oTGNAuZk2KpTdnuJLGIw.jpg
2. If user is in the group, he is a member of event.
So, if he is not a member of event/group, he can join it. Else he can leave this event/group.
I can check current group/event. It works. In my code I know group name - I got it from database.
But when I trying to use $modx->user->isMember() it telling me, that user is not in this group. But I see in database, he is member of this group.
PS: I am telling about webusers, registered buy "Login" snippet.
PPS: I am trying to use groups because I see this is single method to use native MODX features without creating additional tables in database.