The SigmaStudio download page was recently updated to include both a released and a beta version of the tool. However, the version numbers that are shown on this updated page are currently incorrect. The currently-released version of SigmaStudio is still 3.1.20; this is the same as before the page was updated. At this time, the beta version available to download is the same file as the current release.
I'll update this post both when the version numbers on the download page have been corrected and when the new software version is available.