So if you go to the properties of the exe is the digital signatures tab missing?
I just downloaded the file myself to check and it was 125mb download and I have a md5 hash for it of 3F58AB6D345B8EEE4FD49ED3649FA1ED and 131,147,512 bytes in size.
Let me know what yours shows, digital signatures are not suppose to go away, the only time they do is if the file itself is changed in some way.
Shane