We do not have a download file for the latest version (1.5), but you can try downloading it from the developer's site
Download version 0.1.0b from Mac Informer
Version: 0.1.0 β
Date update: May 24, 2016
File name: tormessenger-0.1.0b6-osx64_en-us.dmg
Size: 40.8 MB