I've only taken a brief look at the design documents so I might have more questions later on but for now I have one question. I hope you don't mind me asking about your design decisions

Would you care to elaborate on the thoughts behind the Entity system? To me it seems like a peculiar mixture between traditional inheritance based object hierachy (TCEEntity, TCEPositionableEntity, TCELightEntity...) and then some component design. What makes the destinction that you inherit from TCEEntity to add positionable data but you must add a component to add a mesh to your entity?
I'm sure you guys have discussed this design in your private forums and have your reasons but I'm not quite getting it yet. Some clarification on how you envision entities will be used in your engine would be appreciated? IMO how entities/actors (whatever you want to call them) are handled in a game engine is the most important so I would like to understand how PGDCE will handle them?