Lost Alpha is a free addon for S.T.A.L.K.E.R. - Shadow of Chernobyl.
here are some Full Dynamic Lightning (R2 only) screenshots of Lost Alpha, with Cromm Cruac's Atmosfear weather. Screens speak for themselves. Please do not pay attention to grass shadows, it was tested only with old bins, and we are not yet sure, if we can restore it. :)
NOTE: before someone would start an useless hysteria wave, we keep our own made weather cycles too + add Cromm's 6 new cycles, and that will change dynamically, so those, who wanted to see the old classic (soc vanilla) skyboxes, they can see them, nothing was removed, just expanded :)