Reproduction steps:
1) Open users attached project, proceed to "Generate stuff" scene.
2) If there are no 1,2,3 scenes in the hierarchy hit "add level" GUI button.
3) Alternatively go into scene 1,2,3 and enter playmode.

Observed errors:
For 5.4.0b10
1) !m_UpdateManager->HasSystem (guid)
2) Error adding system: Failed to allocate system.
For 5.3.3p3
Error adding system: Data not available.
1) Error adding system: Data not available.

Reproduced with: 5.4.0b10, 5.3.3p3
Does not reproduce with: 5.2.4f1