Problem:
I downloaded this version (OSDSetupV1.4.5.exe) and tried to install it but right at the end of the installing process it says that it can’t run and Sophos (my anti-virus software) pops up with a Mal/RufTar-c virus and quarantines it. The file that is quarantined is called OSEng.dll and is located in OptiSurface folder.

Solution:
OSEng.dll needs to communicate with our license server and that is why your antivirus software probably quarantined it. Please adjust your antivirus software to allow OSEng.dll access to the internet.