Recently a problem occurred when a colleague was assigning (a lot of) records to different groups.
The computer crashed - for whatever reason. After starting endnote again ALL allocations where gone - no entries in the groups anymore.
After talking to adept scientific I found out that endnote saves the group allocations in the working memory (RAM). But when the computer shuts down the group information is also gone.
A solution would be to implement an auto save function (like word does) - which you can switch on and off manually.