it did not pick them up to the Escort deck.
Is there something in the Latest.log?
Are you sure you maintained target lock on the ship?
Can you reproduce the problem?
I will try to reproduce it, will let you know. Yes, target lock was active since I watched the distance in the lock cursor. Latest lock did not show something suspicious, only that I targeted and untargeted the ships and they did not have the name "Derelict".
When flying close, the Towbar picked them up.
Towbar can pick up usable derelict ships also, but this ship will be salvaged in the next dock. This is an useful feature when your deck is full.
Ok, so that's by design. Good to know. But I believe I remember it did not do that in the past, at least not automatically on <100m distance. Didn't try it with bumping though. But I may be totally wrong on that.
There was an exhibition at the Witchpoint
Exhibited ships are not derelicts so ignored by both Escort Deck and Towbar.
Yes, but legitimate pirate ships which have a pendant in the Exhibition half a system away can also not be picked up (I get the message that's because it is in Exhibition). Other OXPs have this problem too (like Escort Contracts showing two M Compass markers if the escorted mother ship happens to have a pendant in the Exhibition) so I thought that's a common and unresolvable problem with Exhibitions. Is it not?
Anyway when I wrote this sentence above, I was just thinking about the "you can not pick up because it is a ship in exhibition" reasoning, which did not apply.