I took Mar21’s lead and deleted the Swift Framework files from my server through ftp.
I then re-installed the version of the plugin that I got of this forum, through wordpress.
The first time I re-updated and the exact same thing happened, the plug-in disappeared from wordpress and my site was again broken.
I then followed the steps again, but this time I have not updated to version 1.64 which it says is available. My website is now running as it was before.
looking forward to knowing why the problems with the update and it actually working.