At first, thanks for opinions
It seems to be something related with your drivers but if you say that the Hydrax and SkyX demo apps works as expected, then the problem must be something related with the bloom compositor or shadows.
So... I've uploaded two .exe's, one with no bloom and the other one with no shadows:
http://modclub.rigsofrods.com/xavi/Hydr ... hadows.exe
http://modclub.rigsofrods.com/xavi/Hydr ... oBloom.exe
Hope one of them works!
As you say, the implemented 'Bloom' effect is not something like a HDR compositor, it's just for water sun highlights, a very simple an unexpensive compositor, nothing compared with a true HDR system. Anyway SkyX supports true HDR rendering, SkyX::setLightingMode(SkyX::LM_HDR or SkyX::LM_LDR), so... it's perfect for a true HDR rendering app.
About the antialiasing problem, it works as expected on my (two-years-old) 8600GT, so it must be something related with your drivers/graphic card.
About the basic clouds, I've to work on them and add some more light scattering effects like the effect you're talking about, but I will put it in the 0.2 version ToDo.
And about the volumetric clouds, I haven't enabled them in the demo, but don't worry, I'll release a demo showing how to use them in the SkyX 0.1 package
About FPS, I get around 50~60 in 1440x900 - fullscreen with the bloom compositor enabled and 'high quality' texture shadows, something very reasonable if you have present that I obtain about 55~65 with the simple Hydrax demo(No bloom, no shadows, no sky).
Anyway I'll work on Hydrax cpu speed enhancements in the future.
For clouds -> xadhoom reply
And for the sunset/general sky colours, don't worry, SkyX uses a simplified physically model that allows you to modify in real-time(without any kind of speed drop) the sky colours.
Just see SkyX::AtmosphereManager::Options::WaveLength
Anyway, I'll improve the Sky shader in a future. (Using a precomputed texture for speed-up things, etc).