Access to plug in

Yesterday I downloaded Audacity 3.7 and then purchased Guitarstrip. The purchase was successful and I downloaded the file. I ran the install but there is no plugin by this name on my Audacity. 

The Audacity 3.7 upgrade was a mistake as it does not recognize any of my plugins, Audacity or otherwise and I can't find any access to the Muse functions.  I have restored Audacity 3.4.2 but one file that I had saved in 3.7 will not open in 3.4.2. 

I am interested in some of the options offered by Muse, which I had never heard of before, even though I have been on Audacity for years, have all the big boy DAWs and hundreds of third party plugins. 

Please advise how to find and use Muse with Audacity.

Thank you,

Jim Davis