I’ve been trying to use SWISH (SWI-Prolog online), but when I click on the link from the homepage, it just loads continuously without rendering the page. Any advice on this would be very helpful. Thank you.
One of the backends had failed. Normally, the load balancer should move you to a working one. I don’t know whether that was the problem. Worked for me. Anyway, restarted the failed backend.
I have some trouble with calling R in swish,
https://swish.swi-prolog.org/example/Rserve.swinb
says sisocks_error, connection refused.
On one of the backends R server has crashed 
Seems to be fine again. Thanks for warning.