Thanks for answering - the Z trader thing is happening regularly enough that it's definitely the AI doing it, I'll try and get a save where it's actually clear.
The dragons thing- yep, it's an X map.
The outguard thing is in my current game, which was a custom start - not sure what version that was started under since there were quite a few hotfixes recently, so I'll poke it a bit and see if it still happens in a new one.
EDIT: Poking complete: I tested a couple of variants of the Outguard thing, as far as I can tell it only seems to happen in campaigns created by using the lobby option from an existing campaign, and then only for some existing campaigns.
The Zenith trader thing I've put on mantis.