Hi Chrome-Erome, thanks so much for your reply. I'm going to go through the troubleshooting steps, I'm writing this post as I try them.
I am running the 1.0.1.511 version of Civ 5, I have it through Steam & always have internet on, so it should auto update.
I have tried to start the game with the mod "Unofficial Patch & Vanilla Enhancement" or something similar to that with similar settings and it does work.
Also I have not used any other mods apart from CCTPP.
Also Horem, thanks for your reply.
I've tried validating game files, it didn't work
About the Runtime C++ thing, I downloaded this:
http://www.microsoft.com/en-us/download/details.aspx?id=14632
I chose repair, tried again & it didn't work, I chose remove & then installed it. Also doesn't work.
Also tried choosing Direct X9 at startup, that didn't work either.
And now I just reinstalled Civ 5...and still doesn't work. I give up, I'm going to go through the process of elimination through the settings to see what it is.
Oh my god, finally! It was the Rome option, the fact that I had picked the only (I assume) Civ to cause the error is a bit annoying -_- & wasted a lot of my time but oh well, I'll just play with another Civ.
Ah that error still bugs me but meh.
~Abs
Edit: I tried with my original settings & well I still get the error so I guess something else also causes the error.
Edit 2: When setting the game speed to Quick, I also get the error, I also tried changing just the Civ to Rome, speed on Standard, also got the crash.