Thanks for the welcome, although I would rather not have been here ;)
I uninstalled the Windows Store version completely and tried to reinstall it from the Store. It immediately triggered McAfee again and made the install useless. So I had to uninstall again and tried installing the desktop windows version from your site. This didn't result in any errors so I could now use Enpass again.
On your questions, my laptop and McAfee are managed by my employer so i can not exclude Enpass from McAfee detection nor do I think that's a smart suggestion to make to customers.
I tried to paste the data from McAfee here but that resulted in a warning that my message was spam, so can't share that?