It sounds like you installed UE into a folder other than the folder where the main copy of Secret Ops is. This is very important - the only folder from which the game can access TRE files (which contain all the data) is the folder into which the original SO was installed.
Don't worry about corrupting your original SO with UE, either - the two games coexist quite happily in the same folder.
Generally speaking, for UE-related problems, you will probably get an answer here much faster than in the tech forum.