1. yes, u should reinstall with following instructions:
2. is ur system vista or xp sp2?
3a. if xp sp2: to check if ur system is working on multi-proc settings (doesn't have to b multi-proc rly, cause hyperthreading does the same thing on some configs): device manager, processor (how many); if u have more than one proc listed, take a look at task manager and see if u can select afinity for apps; reinstall cf using guide but do not start the game, just report what u did and findings about proc and afinity back here,
3b. if vista: run everything using 'run as administrator' command from app's context menu, following the cf guide instructions, try running the game and updating as stated in the guide, report if u had any success.
do not install 1.1 patch, sdks or anything similar.