Visible crew/equipment: Just after Lockdown stabs Optimus in the chest with his own sword, Cade runs closer and shoots at Lockdown. He then hides behind some bricks. In that shot, the bricks are a broken wall that is two separate pieces. Then it cuts to a different shot as Lockdown returns fire at Cade, and now the wall is one piece. Not only this, but some random guy suddenly appears in the shot next to the wall and right where the explosion happens where Lockdown shot the wall. He is wearing the same color clothes as the wall and only visible for a moment. There was no other guy present until that moment and he just suddenly appears behind Cade and gets hit. It's presumably a special effects member setting off the charge in the wall by the looks of it and it detonated before he got out of the shot. (02:30:55)
Visible crew/equipment: During the finale battle with Lockdown when Shane is driving the truck, you can see the shadow from the filming Go pro on the wheel of the truck. (02:32:35)
Continuity mistake: Optimus and the car Tessa is trapped in are caught in a net and are pulled up to Lockdown's ship. Cade then jumps and grabs onto the net whilst it is being raised. There is a brief moment where Optimus is not visible inside the from the net, before being visible again in the next shot. The CG artists likely forgot to add Optimus into the shot during post-production. (01:22:35)
Revealing mistake: When Galvatron is firing rockets on the Autobots, a flatbed truck swerves into the back of an RV causing it to flip over and explode. There is no driver in the RV. (01:17:40)
Continuity mistake: Lucas returns from getting parts for Optimus Prime, saying he went to the doctor. As he pulls up in his car and parks, his window is up. But then it shows him open his door and climbing out, and suddenly the window is halfway rolled down. (00:33:20)
Continuity mistake: When the girls in the red jeep pull up to the mail boxes, Tessa gets out and says "almost time for a tan and get wasted." Another girl then gets out and throws one arm up in the air and cheers. From the front shot, you see that both her sleeves are still over her shoulders, and her hair is over her left arm, which is down. From behind and the sleeve on her left shoulder is down so her arm is showing, and her hair is now behind her back, with her pink bra strap visible. (00:07:10)
Continuity mistake: When Darcy is at the site in the Arctic, the frozen Dinobots she sees do not appear until she walks up to them. In the establishing shot of the site, they are nowhere in sight. And in the shot where the site worker is pointing a shotgun at her, the only things seen in the background are the vehicles on the site. The frozen Dinobot suddenly appears in the background when she continues to walk towards it. (00:03:05)
Answer: Optimus was being dramatic when he said it contained their memories. Transformers don't carry their memories in their spark any more than humans carry theirs in their soul.
MasterOfAll