The Presenter Plug-in is only available as a 32-bit plugin. It will run fine on 64-bit computers, but it not available for the 64-bit versions of web browsers.
ProShow has been tested with 64-bit versions of Windows, and it works normally. You don’t need to do anything special to use ProShow on these newer systems.
If you do not hear audio when previewing a show in ProShow or when viewing an online show the most likely cause for this is the Presenter player is muted in the volume mixer. Windows Vista and Windows 7/ 8 have a new volume mixer that allows you to mute specific applications and the Presenter is most likely muted.