This is not your usual yoda drunken thread, its a well thought out one.

I sold guns to a Corvus station (it might have been ships) and got basic trader 1. This should not happen, as ships and guns are not trade items.

This, in my honest opinion is a bug.

I don't see the problem. You bought guns, and sold them for a profit. Sounds like trading to me.

Of course, if you didn't buy them, then it's a different matter. It would also clearly be a bug if you didn't make a profit. Indeed, if one couldn't ferry around weapons for profit, THAT would be a bug, because weapons are, unfortunately, quite profitable to deal in.

profit is profit is profit. does not matter what the items.

To be consistent, selling guns and ships should give trade XP.