Steve, thank you for your reply. Wiki says that “VST instruments (VSTi) (such as synths) … are not yet supported. These will not load even if you enable or re-enable them…”, but this AU AUNetReceive plugin gets loaded properly and gets shown in the menu 
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Should then this be reported as a possible bug somewhere? Plugin shouldn’t be shown in menu if it’s not supposed to work, and shouldn’t be listed as an available plugin. Or at least docs/wiki should be updated (I wasn’t able to find a way to edit it).