UPaperTileMap::CloneTileMap Usage

I’m trying to duplicate some tilemaps so that I can change some tiles at runtime.
However when I call TM2->CloneTileMap(this); in my Actor BeginPlay(), I’m getting the following error :

Fatal error: [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.10\Engine\Source\Runtime\Engine\Private\PhysicsEngine\BodySetup.cpp] [Line: 761]
This platform requires cooked packages, and physX data was not cooked into BodySetup /Game/2DSideScrollerCPP/Maps/2DSideScrollerExampleMap.2DSideScrollerExampleMap:PersistentLevel.MapGenerator_11.TestTM2.BodySetup_74.

I did build from the editor, and launched from it. What am I doing wrong ? Is there another way to get a copy of the tilemap ?

Edit: Note that I did cook the project, and that the issue still appears. I tried to use UPaperTileMapComponent::MakeTileMapEditable, and I’m getting the same problem.