Quote: "1. Can we just use the SDK to render objects to the screen, and do we have access to the objects world transforms and triangle indexes if we want to use our own physics engine?"
You can do whatever DBPro does - and that can render objects to the screen. You can access their vertex data by using memblocks IIRC, but that's a bit of a long way round. There are some plugins for DBPro that let you access raw vertex data without memblocks - I don't know whether you cna use it with DarkSDK.
Quote: "2. Does the SDK allow seemless access to the Win32 SDK from within our programs?"
Whatever you can do within normal VIsual C++. DarkSDK is just a collection of functions for c++.
Quote: "3. How are terrains handled are they tiling or just one terrain, and if so, as stated above do we have access to the triangle strips that make up the terrain for manipulation and inclusion within a physics engine?"
You can use matrices, which are tiled and you can adjust each tile height, or heightmap based terrains which are nicer - but you have to manipulate a greyscale heightmap image then recreate the terrain to adjust that in real time (ie no access to height data).
Quote: "4. Is there classes or calls from within DB that support a game based UI? Or do we need to write our own UI classes?"
You'll have to write you own. Really easy though - just load a few sprites
It isn't a complete game sdk as such like Torque which has its own UI etc, that's all left down to the programmer. DarkSDK is a simple, easy way to build anything you want *from scratch*, there's nothing fixed about it.