If I have 10 groups and I “Edit Details” on one of the groups, and change the name, then when I go back to the “Group Summary”, I only see 9 groups listed. Note that “Total Groups” at the top still shows 10 groups, and the group still exists in the system, it just doesn’t show on the “Group Summary” page.
Temporary work-around: If I add a brand new group (which I can then delete afterwards), it will cause the edited group to re-appear in the “Group Summary” page.
The issue showed itself when I was creating groups too (I think I had something like 3 or 4 groups and again I ran into the problem with 7 or 8 groups), so it definitely did not have anything to do with the number of groups.
Just to go out on a limb: all my groups have spaces and parenthesis in their names.* Maybe this has something to do? Or maybe the latest SVN version has already fixed the problem?
Additionally, I found that the act of deleting a group also functions as a workaround, causing the list of groups to update successfully. (in other words: 1. add group11, 2. edit group 10 name, 3. group10 disappears from list, 4. delete group11, 5. group10 now reappears)
Out of curiosity: any reason you said “rooms” instead of “groups”?
*And spaces and dashes in the contact list names (in the group details). This is my naming scheme: