I was trying some things and I think i've made some advances, but I need help because I don't know too much about C.
First, i've made some changes to the webcam to remove those xid problems... xid is something for unix, but on windows it can use "handle" instead, so, added checks for os.name and used xid or handle. (attributes for gtk.gdk.drawable
http://library.gnome.org/devel/pygtk/2.16/class-gdkdrawable.html)
I intalled gstreamer win builds
http://www.gstreamer-winbuild.ylatuya.es/doku.phpAnd tryied to compile all the .c files on libmimic folder.
The two main problems are:
-I don't know what to tell to gstreamer to get the webcam, it uses v4l2src on the code when creating a pipe, but it's only for linux (v4l2 = video 4 linux 2)
-I can't create a .so with all the .o files compiled (i compiled them using "mingw32-gcc.exe file.c -o file.o -I c:/path_to_python's_include_folder")
If anyone can help me here...

I'll post the errors when I get back from work