Sorry for the delay in my answer, but I was terribly busy during these days.
By the way, everything seems resolve....thank you

I copied the 1.2.1.exe inside the folder, then I used it to launch the game. And, indeed, the crush problem vanished.......but now, it doesn't allow me to save games o.O

I searched in my /Programs/Slitherine/CoW folder, but I found no Redist folder....

Reload the files? How can I do it? (I know, I'm a terrible dummy T.T)

Also, I have checked the CoW folder...and Mss32dll is there, apparently...so I don't know why it said to me otherwise...

I'm actually experiencing the same problem as Ivantheterrible: after having noticed that the game crushes after I conquer a city, I downloaded the 1.2.1 patch. However, when I try to run its .exe it says that mss32dll is missing.