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Right, but what I meant is are your members divded between these groups as Primary Users? The first four are obvious, the three below those are your issue.
How many members do you have in each of those three groups (you can see that in your AdminCP area under groups I think. If they get permissions from a secondary group, you have no issues.
Now, this really is not "that" many groups either so you could just add your contributor groups on top of these but remember to add them as "SECONDARY GROUPS" and when their contribution expires they will just lose that secondary group access rights.
There are lots of ways to fix this, but obviously you need to take your time as an oops that loses your custom groups on a big board will drive you insane! I assume you are doing backups before you start messing with the database, right