If you had the full version (which i assume), it changed back to the free version after reinstallation.
Check
http://forum.thegamecreators.com/?m=forum_view&t=154050&b=28 for more info.
Short version, you are missing a (licensed)name and serial number in your userdetails.ini, most probably its empty when you check.
Without this info, FPSC handles like its a free version. Fill in this info, restart FPSC and your Build Game option should be back
The free version doesnt have Build Game, thats why your missing that option.
Grts
Anubis
-+- There are only 10 types of people in the world. Those who understand binary, and those who don't -+-
[Chipset:X58 CPU:i7.950.64 GPU:HD5970 RAM:12GB DDR3 WIN:7.x64 PRO FPSC:1.20.10]