Nickname dialog is broken

Steps:

1. invite new external user by entering email only
2. enter to OM using invitation link
3. in NickName dialog enter first/last name
4. click OK
   Result: dialog is closed username in user list is not changed
   Expected result: dialog is closed entered first/last name is displayed in user list for all users

Additional issues:

1. NullStringer need to be used for room options
2. first/last name in activities
3. Title of video window