Hello and welcome on the forums,
There was more action on the forums but I've moved to a new server and had to set new forums, because the old one wasn't compatible with new one.
1) Yes it's fully c++ based, it has some Assembler optimizations, and shaders are created in HLSL.
2) Yes it'll be ready soon, right now only terrain is managed automatically, objects will be next.
3) You can check the "Features" documentation to see what exactly is available out of the box. You have access to graphics, sounds, rendering, controls, io, physics, there are some pure gaming interfaces as well, you can create a character, control it manually or order to fulfill some automatic actions. camera is fully controllable.
4) it's more class driven (B) however some functions are in (A) way. Each function has been carefully designed to have easiest usage and fastest speed possible.
5) could you be more specific with your question?
Is it ready for a game? Sure, if you'll need some additional features let me know, and I'll implement them.
As a bonus I can say that currently I'm working on documentation, soon it will be much better, and more detailed
Let me know if you have more questions.
About importing models please try drag and drop the file on the Mesh Editor window