I'm just testing your new plugin Private Messaging but it's not working properly on my WP 4.1 install.
In my wp dashboard > messaging > settings, I only see the settings page flashing up and then it's gone; leaving an almost blank settings page.
I've switched off all plugins, reverted back to default theme (child-theme was activated) and Private Messaging worked. It stopped working when I re-activated the child-theme.
Could you make this work for the child-theme?
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