Soundtouch App for Mac

I had the sound touch App on my older Mac, why will you not let me download the app from the Bose website. Is the a way to work around the BS “SoundTouch-osx-installer” can’t be opened because Apple cannot check it for malicious software. It's my computer and I'd like to use it. It's bad enough that when you download any music from iTunes you just rent it, Im done with that, still buyingCD's. Yes there is anger here.