The cause to your issues is directly related to the upgrades. According to the data found on the official website, the latest version of the software is 1.4.0.1 and it was released on 7 February 2016. The latest version also supports the following Windows versions: Windows XP, Vista, 7, 8, 10 (32-bit and 64-bit).
Download the latest version through the link: http://www.wolfcoders.com/screensnag/