Does UE4 Source Code has all the information? Please HELP!

I would really want to know is there anything else that i am missing source code folder and intermediate(which stores shaders) folder have all the information in them,if i want to lets say if I wanted my game to take advantage of more processor cores and say I want my game to be optimized for SLI or CROSSFIRE and I am able to modify how unreal Lighting ,Rendering and shaders work? Am I correct?
And one more question - Is it like that Source contains all information about shaders like how to create them or modify them, but they are stored in Intermediate folder?
I should be able to do this type of stuff - as in Bioshock Infinite - Critically Acclaimed BioShock Infinite Powered By Unreal Engine 3 Technology
And how can I integrate Nvidia Gameworks in my game - Game Development Tools, SDKs, and Partner Engines | NVIDIA Developer
Please HELP!!!

Having the full source let’s you basically to what ever you want (or can), parallel rendering (which should be in sometime I think, or it is already) will give you quite a boost in rendering performance. With the source you get all.

There is already a thread about Gameworks, specially a working WaveWorks integration.

Is it like that Source folder contains all information about shaders like how to create them or modify them, but they are stored in Intermediate folder?
Am I correct?

Am I RIGHT!!?

Calm down. Acting like that is not how you ask for help. Don’t expect immediate answers, everyone has their own schedules.

Anyway, the intermediate folder is for generated files: files that the build tool creates. Shaders (and all other files) in this folder are autogenerated and should not be modified directly. If you want to see the hand-created shaders, look for usf files, especially in Engine/Shaders in the source tree.

Theoretically, you can make whatever changes you need to, but you need the knowledge and the experience to do so correctly. That kind of skill does not come quickly, and you should be prepared to be patient and persevere for quite some time.