First, download the community guide and read through it. The guide can be found here:
http://forum.thegamecreators.com/?m=forum_view&t=131868&b=21
For what you're asking, go to FILE > PREFERENCES. For best effects, make sure you have 'full light mapping', and 'High 512x512' texture quality selected.
If you're still not happy with texture/"shadows" quality, go into the FPSC Directory on your computer here:
C:/Program Files/The Game Creators/FPS Creator
Look for the setup file, and under [GAMEMAKE] you'll see these two lines:
lightmaptexsize=512
lightmapquality=100
Make sure they say 512, and 100. Save, close FPS Creator, and rebuild your game.
*NOTE* If you're using dynamic lights (green outline in the editor), they won't cast any shadows. Only static lights create shadows. Good luck.
-Kravenwolf
Success is not final--failure is not eternal.