I completed the Pride & Peddlers and got the gold medal. After completing it the game showed it as received, but now it only shows as if I had only got bronze and silver. I cannot use the reward either; I can only select the skin for the cross-shaped museum building and the rectangular one, but not for the rotunda one.
The bug might've been triggered due to me loading the save game of the scenario after getting the gold medal. (Unfortunately I didn't test the rewards in a normal game before that.) But naturally it shouldn't do that. And it doesn't give it to me if I try completing it again from the moment just before winning the scenario. (This might also have been a problem with the A Clash of Couriers, but I don't dare to test, to not lose the gold medal I already got.)
(Note: I did complete it straight for gold medal; I did not try recompleting a save which I had already won and trying to "upgrade" the medal. It was the first time I completed this save when I got the gold medal.)
This might be related to the fact that during the game it showed the bronze and silver medals as if they were completed, even before I had bought the three items from the traders. It shouldn't have, as all the medals can only be completed by placing all the three items in the museum. It showed that in the loading screen, on the left sidebar during the game and in the mission briefing view (for the last one, see a screenshot below).
I really wouldn't want to try running again for the gold. It was an immensely dull goal. After shipping 100,000 tons I had already got my economy sustainable even after market crash after market crash and I knew how to bank savings to cope with those, but I still had to wait for a couple of hours for the trading to get to 500,000 tons, even on max speed. So it wasn't in any way difficult to get after that point, just a matter of patience, i.e. not fun at all. I'm now going to replay the scenario, as for its beginning it's quite fun, but I don't want to go through that hours of waiting again.
Here's the save file: https://1drv.ms/u/s!AqHfqBwyVV-1rukAmlFumbcl_KDYWQ?e=G2gyJx: (https://1drv.ms/u/s!AqHfqBwyVV-1rukAmlFumbcl_KDYWQ?e=G2gyJx)
Here's a screenshot of me getting the gold medal (also note the incorrect text; I mentioned it on another thread already):
And here's one how it looks like now:
Here's how it was showed during the game, even before completing it for the first time for any medal: