>>Blitz3D is already a game engine. <<
If by definition of game engine we have to assume something like "The core functionality typically provided by a game engine includes a rendering engine (“renderer”) for 2D or 3D graphics, a physics engine , sound, scripting, animation, artificial intelligence, networking, streaming, memory management, threading, and a scene graph." , Then we can also assume that B3D missing majority of things listed and far as i can see it, its programming language wrapped around DX7..there is no out of box solution such as AI, Physics, Network ... so you have to use 3rd party libs or build your own...so, it cant fit in to game engine category at all..
If by definition of game engine we have to assume something like "The core functionality typically provided by a game engine includes a rendering engine (“renderer”) for 2D or 3D graphics, a physics engine , sound, scripting, animation, artificial intelligence, networking, streaming, memory management, threading, and a scene graph." , Then we can also assume that B3D missing majority of things listed and far as i can see it, its programming language wrapped around DX7..there is no out of box solution such as AI, Physics, Network ... so you have to use 3rd party libs or build your own...so, it cant fit in to game engine category at all..