I tried to port some old WDL-Code to Lite-C. I used a sky definition with speed_u/speed_v parameters. They seem not to work in Lite-C but there is no error message nither. Here is the code:
ENTITY* clouds_night= { type="clouds.tga"; layer=3; speed_u=4; speed_v=6; alpha=70; flags2=SKY | DOME | SHOW | TRANSLUCENT; }