4K Slideshow Maker won't work on Mac OS Yosemite

I am using mac OS X 10.10.5, and am trying to use 4K Slideshow Maker, but the icon has a 'no' bar over it and it won't let me import photos. (the correct red icon also does not appear, the icon looks like a generic page).

The 4K Downloader and Youtube to MP3 work fine, but not the Slideshow Maker. I tried disabling the auto 'don't open software by unrecognized developers', but that didn't help. Is there an updated version somewhere? Thanks, Rick.Garside@gmail.com