The best way to play swf files is with the official flash player, there are some other open source projects, but they seem to either not work at all or are too cumbersome to use as a simple tool that plays flash files. The link below serves all the debug programs for adobe flash player, including a stand alone executable that will play raw swf files. The links are a bit unclear as to what they are, the correct program needed is the Flash Player projector.

https://www.adobe.com/support/flashplayer/debug_downloads.html