Hi, it's been a year that vimeo.com doesn't work in slimjet. I used the "Online Feedback" option at the browser to report it a couple of times but I'm not sure if you received it.
Click here for example:
https://vimeo.com/35982411
It doesn't even show the thumbnail of the video.
I hope you can do something about it.
OS: Windows 7, 64 bit
Version 23.0.6.0 (based on Chromium 74.0.3729.108) (Official Build) (32-bit)