I've come across something that I'm very unsure of if it's a bug or not.
At the brony site there's a challenge right on the deck of the wreck. It's a group shot (1x bucket, 1x bell and 3x rusty cannon). When I accept it I don't get an objective marker but I can't find the site at all. I've searched inside the wreck and in a large radius around it. Did I just miss it or is it really not there?
I just tried that mission and it appears to be a bug. I could find the objective marker by pressing TAB +1, but it took me away from the ship. If I remember right, the objective was right down the hatch near the mission tank. There was an update to that level recently, so maybe the bug was introduced then. You should report this in the bug forum, or maybe one of the mods can move this topic there.
Good find Dottedfish. Can confirm this challenge is currently bugged.
The objective doesn't show up on the diving computer. The location at which the objective items used to spawn remains empty at the moment.
They used to spawn inside the cargo hold of the ship. I'm not aware of an alternate location for them. Be sure to post about this in the bug section.
I can confirm that bug too, was looking for the items all over, and they are not shown in GPS, the only mission I could not finish...
That photo mission is still buggy, tried it again but could not find the 3 needed objects at one spot and the marker just points to the air bottles for the mission: