Reproduction steps:
1. Open attached project
2. Build and run the project (set it as host)
3. Open and play the "offline" scene
4. Join the host form the editor
5. Error should appear in console: "HLAPI CRC channel count error local: 0 remote: 1"

NOTE: When adding the "GameManager" prefab to the "Registered Spawnable prefabs" error doesn't appear. In 5.3.0b3 when adding the "GameManager" prefab to the "Registered Spawnable prefabs" and then following the reproduction steps Unity will crash.

Regression from first not working version: 5.2.0f1 (89160207ce1a)