Well, your mod can at least help somewhat to get those curios enough to register.
And just to mention, there's some minor spelling errors, nothing that impacts the way the mod works (or I didn't noticed that for the moment).
For example:
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So by setting this to "Yes" you will stop
dmins and moderators from being able to reply to closed threads.
Note: Of course this will only work if the selected usergroups are
a admin or moderator group.
Set this to "Yes" to
chow a thread closed image in the closed reason block.
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As you can see, nothing big, but just to mention...