I try to download Mdk472_a.exe, but it stopped at 60-70% (after a few hours) with the message of "publisher of this program could not be verified." I lowered the Internet security level and disabled several checks, the download still stopped without finishing. Could someone help? Thanks.
If the source code contains comments or strings of the type "crackz", "hackz", "warez", "serialz", "appz", "MBR", "Master Boot Record", "partition table", "/etc/shadow", ... then you know it was a bad idea to use the program.
In short? You either trust the program or you limit the program use to programs you compile yourself from source code you completely understand. If you don't understand the source then it doesn't help you to have access to it - then you just have to trust others to have read, and understood, the source.