I tried 6 standard web hosters to get this thing up and running, and on the 6th, it finally worked. I don’t know what the fault is, maybe some PHP configurations, but other scripts and content management systems do work fine. And by the way, no success in my local Apache/PHP environment either.
The support could solve only one cookie problem, but that did not lead to success, as the installer just showed a blank page in most cases.
Well, I found another comment script, which does not make any problems. But it is, unlike easyComment, not built on the terrible Laravel framework, which I had problems with in some earlier cases.
No refund so far for this software, which I cannot use on one of my two paid webspaces.