Yes you can..

1 you can use an environment probe and tweak the settings to suit.
2 See cvar list and find the ones you need to improve on shadows and other things. + yes there is extra settings in either trackview or time of day.
3 yes but the reflections will need sorting.
4 just render inside a cylinder or room then add in lights and other elements to get the results you want.

sure you can

1.


2.


3. Set distanceCloud shader for material of the sphere and tick simple distance clouds checkbox in shader generation params

4. Place your HDRI in Diffuse slot of your sphere material, place sphere on level, remove ocean, hide terrain

5. Put one big Environment probe in level and generate

6. Done

Very helpful stuff! Thx for this tutorial @mindrevolution !

Oh!
whats with the Transparency, Can i make a render with transparent Background or with a Mask of the Asset so i can delete the background manually in Photoshop ?

Dont know exacly, but i think no, cryengine dont have ability to make screenshots with Gbuffer passes or custom depth mask like ue4, if you want compose them later in AE, etc...

You can use a Green Screen method, although post processing in an external image application would be necessary to perfect the image.
The idea is to use a plane or box (any object) and set the material to a pure green texture using the "ReferenceImage" shader to fill the background.

For example;