How can I find out if a certain file is a false positive or not?

Hi, my name is Bob. I have a question reguarding a file that Webroot has detected as a w32.malware.gen threat, when extracting a game engine tool. The file came with a game engine, called Torque3D, and I am most positive that the file is a false positive. However,  I have searched GarageGames forum, Torque3d.org forum, and Google, which  I could not find anything from any of these search engines returning results about the file. Usually when doing a file search on google it will have results from piticular communities discusing about the piticular file. However, I could not find anything on it. So I am still not fully 100%, and I was wondering how I could find out if the file is a false positvie or not? For anyone who wants to know the filename, it is called bzip2_solid.zip.