I do not see the difference between invoke vs cinvoke?
invoke n cinvoke in my machine return one value
my asembler version is 1.69.25

you definetly have to learn what is calling conventions and what kind of calling methods are using mostly.
to say fast, there are two main ways: stdcall and c-call. for stdcall called procedure must restore stack, for c-call caller must restore stack. c-call is used mostly for variable number of function parameters in stack.
if your improper code occasionally works - say thanks to uncle Billy, as system checks stack after return from window procedure and tries to restore it if improper for console application of two function calls it may appear invisible, but may give hidden trouble somewhere if missed
regards!

pearlz: For that small example you are using the "c"invoke won't make any difference because you are immediately calling ExitProcess and the OS will clean everything up. But once you start to use that code in a real application then things can start to go haywire because your stack gets messed up.

BTW: wsprintf is the ONLY Win32 API function that needs cinvoke. All the others use invoke.