Basically need to know if anyone can tell me how to install a new scenario after I have downloaded it off this site?

Cheers

If there's not instructions that came with it in the forum of a readme.txt or in the first post of the thread you d/l'd it from, I'd ask in it's thread.

And since you've already asked here (http://forums.civfanatics.com/showthread.php?t=226040), thread closed. Please refrain from creating multiple threads for the same problem.