Curious.
MD5 is a hashing algorythm commonly used to create hashes of a file, to allow the downloader to check its integrity.
So the MD5 file is offered sometimes along with the main file to allow such check.
Is it possible that you mistook an hash file for its corresponding exe file?
Anyway, I am unable to find references to MD5 hashes in the SkySimulations website.
Unless of course MD5 stands for McDonnel-Douglas 5
