If a scenario has one or more palette defined on the pickupStack, we'll have to pick these up and store them somewhere in order for the scenario to be complete at the end of the simulation.
If you run the scenario below, it will fail. We've picked up a palette and navigated adjacent to an empty stack, but we've not stored the palette. Try adding the instruction 0 store 3.5.Z, where Z is between 0 and 6, and run it again.