There's a crash when you have nothing in the current slot, but attempt to place it on a ship in build mode.
```
java.lang.NullPointerException: Exception: REQUESTED TYPE 0 IS NULL
at org.schema.game.common.data.element.ElementKeyMap.getInfo(ElementKeyMap.java:635)
at org.schema.game.client.controller.manager.ingame.PlayerInteractionControlManager.buildBlock(PlayerInteractionControlManager.java:197)
at org.schema.game.client.controller.manager.ingame.SegmentBuildController.buildButtonPressed(SegmentBuildController.java:426)
at org.schema.game.client.controller.manager.ingame.SegmentBuildController.handleMouseEvent(SegmentBuildController.java:379)
at org.schema.game.client.controller.manager.AbstractControlManager.handleMouseEvent(AbstractControlManager.java:281)
at org.schema.game.client.controller.manager.ingame.ship.ShipControllerManager.handleMouseEvent(ShipControllerManager.java:89)
at org.schema.game.client.controller.manager.AbstractControlManager.handleMouseEvent(AbstractControlManager.java:281)
at org.schema.game.client.controller.manager.AbstractControlManager.handleMouseEvent(AbstractControlManager.java:281)
at org.schema.game.client.controller.manager.ingame.PlayerInteractionControlManager.handleMouseEvent(PlayerInteractionControlManager.java:1256)
at org.schema.game.client.controller.manager.AbstractControlManager.handleMouseEvent(AbstractControlManager.java:281)
at org.schema.game.client.controller.manager.AbstractControlManager.handleMouseEvent(AbstractControlManager.java:281)
at org.schema.game.client.controller.manager.ingame.InGameControlManager.handleMouseEvent(InGameControlManager.java:319)
at org.schema.game.client.controller.manager.AbstractControlManager.handleMouseEvent(AbstractControlManager.java:281)
at org.schema.game.client.controller.manager.GlobalGameControlManager.handleMouseEvent(GlobalGameControlManager.java:249)
at org.schema.game.client.controller.GameClientController.updateInput(GameClientController.java:3255)
at org.schema.game.client.controller.GameClientController.updateStateInput(GameClientController.java:3014)
at org.schema.schine.graphicsengine.core.GLFrame.start(GLFrame.java:1014)
at org.schema.schine.graphicsengine.core.GLFrame.startGraphics(GLFrame.java:1181)
at org.schema.game.client.controller.GameClientController.startGraphics(GameClientController.java:2329)
at org.schema.game.common.ClientRunnable.run(ClientRunnable.java:86)
at java.lang.Thread.run(Thread.java:662)
```